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The Map of Hogwarts and Surrounding Areas: the Forbidden Forest
Analysis Flora Fauna Layout
Conclusion Criteria which must be met Map of Forbidden Forest & its position
As discussed in the section on Setting and the Forbidden Forest section of the essay on the Hogwarts grounds, the Forbidden Forest lies west and north-west of Hogwarts castle; possibly due north and/or south-west as well, but we have no information on that. There is a mountain to the north-west of Hogwarts, and this may well form the boundary of the Forest in that direction. Since the mountain is only about a mile from the school, and the Forest is certainly more than a mile wide, then it either flows around the base of the mountain, or to some extent climbs it, or it extends into wizard-space.
At the point where it meets the Hogwarts grounds it swings round in several large curves, including concave curves in the vicinity of the Whomping Willow, Hagrid's cabin and the Hippogriff/dragon paddock, and a convex curve in between Hagrid's cabin and the front gates. Its trees where it meets the Hogwarts grounds are mostly well-grown and dark, and most areas of the Forest are primarily deciduous - except for the swathe of pine trees between the station and the lake, which may or may not be contiguous with the Forest proper.
In the weeks that followed [Quirrell] did seem to be getting paler and thinner [cut] 'Hermione, the exams are ages away.' 'Ten weeks,' Hermione snapped. [cut] Unfortunately the teachers seemed to be thinking along the same lines as Hermione. They piled so much homework on them that the Easter holidays weren't nearly as much fun as the Christmas ones. [PS ch. #14; p. 167]
Every now and then a ray of moonlight through the branches above lit a spot of silver-blue blood on the fallen leaves. [PS ch. #15; p. 183]
Hagrid seized Harry and Hermione and hoisted them off the path behind a towering oak. He pulled out an arrow and fitted it into his crossbow, raising it, ready to fire. The three of them listened. Something was slithering over dead leaves nearby: [cut] after a few seconds, the sound faded away. [PS ch. #15; p. 183/184]
[cut] they couldn't hear anything but the rustling of leaves around them. [PS ch. #15; p. 186]
Harry could see a clearing ahead, through the tangled branches of an ancient oak. [PS ch. #15; p. 186]
[cut] its mane was spread pearly white on the dark leaves. [PS ch. #15; p. 186/187]
They walked behind them for about twenty minutes, not speaking, listening hard for noises other than breaking twigs and rustling leaves. Then, when the trees had become thicker than ever, so that the stars overhead were no longer visible, and Harry's wand shone alone in the sea of dark, they saw their spider guides leaving the path. [cut] So they followed the darting shadows of the spiders into the trees. They couldn't move very quickly now; there were tree roots and stumps in their way, barely visible in the near blackness. Harry could feel Fang's hot breath on his hand. [cut] They walked for what seemed like at least half an hour, their robes snagging on low-slung branches and brambles. [CoS ch. #15; p. 202]
Fang yelped and tried to run, but got lodged in a tangle of thorns and yelped even louder. [CoS ch. #15; p. 203]
He never knew how long he was in the creature's clutches; he only knew that the darkness suddenly lifted enough for him to see that the leaf-strewn ground was now swarming with spiders. [CoS ch. #15; p. 204]
They smashed their way through the undergrowth, Fang howling loudly in the back seat, and Harry saw the wing mirror snap off as they squeezed past a large oak. [CoS ch. #15; p. 207]
And then, as Hagrid shook his hair back for a third time and expanded his enormous chest, Harry nudged Ron and pointed into the black space between two gnarled yew trees. [OotP ch. #21; p. 393]
'Firenze said they're angry because he went to work for Dumbledore,' Harry said, tripping on a protruding root because he was busy watching Hagrid's profile. [cut] 'Yep,' said Hagrid gruffly, forcing his way through several low-hanging branches. [OotP ch. #30; p. 605]
'Hagrid!' said Harry, fighting his way through thickly knotted brambles, over which Hagrid had stepped with ease, and remembering very vividly what had happened to him on the other occasion he had stepped off the Forest path. [cut] It was a great struggle to keep up with Hagrid, what with branches and thickets of thorn through which Hagrid marched as easily as if they were cobwebs, but which snagged Harry and Hermione's robes, frequently entangling them so severely that they had to stop for minutes at a time to free themselves. Harry's arms and legs were soon covered in small cuts and scratches. [OotP ch. #30; p. 606]
[cut] 'jus' a little bit further through here ... watch yerselves, now, there's nettles [OotP ch. #30; p. 608]
Grawp reached out a hand the size of a beach umbrella, seized a bird's nest from the upper branches of a towering pine and turned it upside-down with a roar of apparent displeasure that there was no bird in it [cut] [cut] He had now seized the top of the pine tree and was pulling it towards him [cut] The giant let go of the top of the tree, which swayed alarmingly and deluged Hagrid with a rain of pine needles, and looked down. [OotP ch. #30; p. 613]
[cut] Harry and Hermione were struggling through a patch of thick knotgrass behind him. [OotP ch. #30; p. 614]
'Hagrid,' said Hermione breathlessly, skirting the patch of nettles they had passed on their way there [OotP ch. #30; p. 616]
'Well, he has,' said Hermione firmly. 'Grawp [cut] enjoys ripping up twenty-foot pine trees [OotP ch. #31; p. 622]
'Is it very far in?' Umbridge asked, as her robe ripped on a bramble. [cut] 'Oh yes,' she said in a steely voice, crashing through the undergrowth with what he thought was a wholly unnecessary amount of noise [OotP ch. #33; p. 663]
[cut] he realised that this was not the Forbidden Forest: the trees looked younger, they were more widely spaced, the ground clearer. [DH ch. #14; p. 221]
'Where are we?' 'In the woods where they held the Quidditch World Cup,' said Hermione. [DH ch. #14; p. 224]
Hagrid's hut loomed out of the darkness. There were no lights, [cut] He moved on, and now he reached the edge of the Forest, and he stopped. [DH ch. #34; p. 559]
[cut] he heard slight movements around him that suggested frail bodies shifting their footing on the earthy, twig-strewn ground that marked the outer edge of the Forest. [DH ch. #34; p. 560]
[cut] together they marched through the old trees that grew closely together, their branches tangled, their roots gnarled and twisted underfoot [cut] travelling deeper and deeper into the Forest [DH ch. #34; p. 561]
The victorious procession marched on towards the open ground, and after a while Harry could tell, by the lightening of the darkness through his closed eyelids, that the trees were beginning to thin. [DH ch. #36; p. 583]
The Forest proper seems to be a mixture of deciduous and evergreen trees. Harry follows Snape into the Forest, to a "shadowy clearing" where he meets with Quirrell, and hides in a beech tree to watch them. Snape has entered the Forest at a point which is visible from somewhere above wherever the broomshed is (which is probably to the left of the front doors as you face them, for reasons explained in the essay on Hogwarts itself), and probably goes a hundred yards or more in, since he entered the Forest at a run, which you would hardly expect if he was only going a few feet in. The wood at this point is apparently deciduous (the beech tree certainly is) and very dense.
Given the extreme density of the trees, and the fact that Snape was moving at speed, there is probably a path to this clearing, or at least a way through the trees which Snape knows well. However, it is probably not accessed from the main, forked path which we see Harry take several times. To get from the castle to the forked path in DH Harry passes Hagrid's hut. Hagrid's hut is at the edge of the Forest and for reasons explained in the section on the grounds), we know from the time it takes to get there that Hagrid's hut is 300-400 yards from the main doors - but we also don't want the nearest edge of the Forest to be more than about 200 yards maximum from the castle, because Harry is able to look out of his dorm window and identify Crookshanks at the edge of the Forest in very poor lighting conditions. So Hagrid's hut cannot be directly in front of the castle - it's well out to the side towards the gates. It certainly sounds as though Snape enters the Forest at the nearest point he can, rather than going hundreds of yards to the left, so he didn't use the path near Hagrid's hut.
This beech tree by Snape's clearing, incidentally, had leaves on it thick enough to obscure Harry's view, very early in the year. At the start of the following chapter, chapter #14, it says "In the weeks that followed", so that takes us up to at least two weeks after the Forest scene; and then just after that Hermione says the exams are ten weeks away. Plus it's still before Easter when she says it, because the Easter holidays are mentioned as being afterwards. Easter in 1992 was 17th-19th April, so even if the exams were well into June the leaf incident cannot be later than 3rd April. And in fact the exams are normally early in June, which would mean this Forest scene was at the end of March. Beech trees do sometimes retain some leaves throughout winter but they are few and shrivelled, unlikely to obstruct Harry's view; it certainly sounds as if it is whole, living leaves which are being referred to. Beech leaves don't normally even emerge from the bud until late April - so either Hogwarts has its own peculiar microclimate or we must be in the far west, where plants do tend to come out earlier.
When Hagrid takes the children into the Forest in PS, they encounter oak trees and a carpet of fallen leaves (not needles), referred to at several points on their journey, so again they are in mainly deciduous wood.
In DH Harry stops to use the Resurrection Stone at the very edge of the Forest, and he hears the spirits he has summoned shifting their feet on twig-strewn ground - so we know the ground at the edge of the trees is twig-strewn and the twigs are dry, crunchy ones, which again suggests deciduous rather than coniferous woods.
In CoS when Harry and Ron follow the spiders they encounter more leaves, trees with low-growing branches (which are probably deciduous, although yews do grow quite close to the ground) and brambles (more likely in deciduous than coniferous woods), and generally thick undergrowth.
Note that the word "forest" does not only mean an area of dense woodland, but also incoporates any more open scrubland which may occur in a generally wooded area, or any wild land which was formerly a Mediaeval hunting preserve. The references to brambles and knotgrass in the Forbidden Forest suggest there are areas of it which are comparatively open and covered more with undergrowth than with trees, even though most of it is thickly wooded.
In DH we are told that the trees of the Forbidden Forest are older and more closely spaced, the ground more densely-covered, than is true of the wood near where the Quidditch World Cup was held in GoF (that, however, did seem to be a fairly open wood - a lot of people were moving about in it, and could see each other). As you go deep into the Forbidden Forest the trees are not only old and close-set but also have tangled branches and gnarled, twisted roots. Towards the edge, however, they are wider-set, so that there is a visible difference in the amount of light getting through them even before dawn.
This last scene, from the Death Eaters' march through the woods with not-dead-really!Harry in DH, again sugests a primarily deciduous wood. The march takes place in early May. It is over an hour before dawn, so any ambient light must be moonlight or firelight. Yet there is enough light getting through the trees that Harry can distinguish measurable differences in light-levels through his closed eyelids. That wouldn't work in a coniferous wood, but in a deciduous wood in early May many of the trees would be in bud rather than in full leaf, allowing more light through.
We are told several times that in the deeper areas of the wood the branches of the trees grow low enough to obstruct Hagrid (who is around 11ft tall) or to obstruct a boy on horse (= centaur) back. This does not rule out conifers, but it does rule out the sort of towering coniferous wood where the branches begin well above the ground.
'Yep,' said Hagrid gruffly, forcing his way through several low-hanging branches. [OotP ch. #30; p. 605]
[cut] Hagrid stumbled forwards, forcing his way through the close-growing trees, back through the Forest. Branches caught at Harry's hair and robes [DH ch. #36; p. 582]
Young Scots Pines near Huntly, Aberdeenshire, with Fourman Hill in the distance © Anne Burgess at Geograph When Hagrid takes the class to see the Thestrals, we get our first glimpse of conifers, in the form of two elderly yews, and later when he takes the Trio to meet Grawp they push through more low-hanging branches and thickets of brambles, nettles and knotgrass to come to an area of small pine trees. [The description refers to a "towering pine" and then specifies it as twenty foot tall, which is tiny for a pine tree.] Again, when they take Umbridge to the centaurs, there are more brambles and general undergrowth. If Hogwarts is meant to be in the Highlands, incidentally, this is a very peculiar sort of woodland. Woods in the Highlands are normally coniferous, and even where deciduous woods occur they are primarily silver birch: Birches in Glen Tilt, Perth & Kinross © Gordon Hatton at Geograph one type of deciduous tree which has never been mentioned in relation to Hogwarts. This is one of the points in favour of Hogwarts being in Galloway rather than the Highlands, although there are some other points, mainly to do with the journey-time, which favour the Highlands - see separate essay on the location of Hogwarts. Good images of the sort of dense, dark wood the Forbidden Forest seems to be are by their very nature hard to come by: either they're too dark to take a shot, or the flash-gun makes them look artificially open and sunny. But here below is a selection of images of mature British woodland, mainly in Scotland, which should give some idea of how the Forest would look. Beeches at Castramont Wood, near Gatehouse of Fleet, Galloway © Callum Black at Geograph Reenadinna Yew Wood, Killarney, Ireland © Nigel Cox at Geograph Old woodland near Merton, Devon © David Brinicombe at Geograph Bracken, oaks and beeches at Castramont Wood, near Gatehouse of Fleet, Galloway © M J Richardson at Geograph Offa\'s Dyke Path through Candy Wood, near Croesau Bach, Shropshire © Tim Heaton at Geograph Mature, well-established Scots Pine in Bogbain Woods, near Inverness © George Brown at Geograph Old growth at Withycombe Scruffets, near Dunster, Somerset © Nigel Chadwick at Geograph
Again, when they take Umbridge to the centaurs, there are more brambles and general undergrowth.
If Hogwarts is meant to be in the Highlands, incidentally, this is a very peculiar sort of woodland. Woods in the Highlands are normally coniferous, and even where deciduous woods occur they are primarily silver birch: Birches in Glen Tilt, Perth & Kinross © Gordon Hatton at Geograph one type of deciduous tree which has never been mentioned in relation to Hogwarts. This is one of the points in favour of Hogwarts being in Galloway rather than the Highlands, although there are some other points, mainly to do with the journey-time, which favour the Highlands - see separate essay on the location of Hogwarts. Good images of the sort of dense, dark wood the Forbidden Forest seems to be are by their very nature hard to come by: either they're too dark to take a shot, or the flash-gun makes them look artificially open and sunny. But here below is a selection of images of mature British woodland, mainly in Scotland, which should give some idea of how the Forest would look. Beeches at Castramont Wood, near Gatehouse of Fleet, Galloway © Callum Black at Geograph Reenadinna Yew Wood, Killarney, Ireland © Nigel Cox at Geograph Old woodland near Merton, Devon © David Brinicombe at Geograph Bracken, oaks and beeches at Castramont Wood, near Gatehouse of Fleet, Galloway © M J Richardson at Geograph Offa\'s Dyke Path through Candy Wood, near Croesau Bach, Shropshire © Tim Heaton at Geograph Mature, well-established Scots Pine in Bogbain Woods, near Inverness © George Brown at Geograph
Good images of the sort of dense, dark wood the Forbidden Forest seems to be are by their very nature hard to come by: either they're too dark to take a shot, or the flash-gun makes them look artificially open and sunny. But here below is a selection of images of mature British woodland, mainly in Scotland, which should give some idea of how the Forest would look.
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Various types of creature are mentioned as living in the Forbidden Forest, some magical, some not. We have unicorns (which can grow pretty large - Ollivander mentions one that was seventeen hands high, which is 5'8" at the shoulders), centaurs, Thestrals (who we know to be omnivores), Hippogriffs (on occasion), trolls, a large population of Acromantulas, deer and assorted birds. The centaurs are obviously quite a large community, since we see fifty together at one time.
‘Ah, now, this is one of mine, isn’t it?’ said Mr Ollivander, with much more enthusiasm, as Cedric handed over his wand. ‘Yes, I remember it well. Containing a single hair from the tail of a particularly fine male unicorn ... must have been seventeen hands; nearly gored me with his horn after I plucked his tail.' [GoF ch. #18; p. 271]
Professor Grubbly-Plank [cut] led them [cut] towards a tree on the edge of the Forest, where a large and beautiful unicorn was tethered. [cut] The unicorn was so brightly white it made the snow all around look grey. It was pawing the ground nervously with its golden hooves, and throwing back its horned head. [GoF ch. #24; p. 379/380]
Today he had managed to capture two unicorn foals. Unlike full-grown unicorns, they were pure gold. ‘Easier ter spot than the adults,’ Hagrid told the class. ‘They turn silver when they’re abou’ two years old, an’ they grow horns at aroun’ four. Don’ go pure white till they’re full-grown, round about seven. They’re a bit more trustin’ when they’re babies' [GoF ch. #26; p. 420]
A man's naked torso seemed for an instant to be floating towards them through the dappled green half-light; then they saw that his waist joined smoothly into a horse's chestnut body. This centaur had a proud, high-cheekboned face and long black hair. [cut] The trees behind the centaur rustled and four or five more centaurs emerged behind him. [OotP ch. #30; p. 614/615]
But they did not hear what else centaurs were, for at that moment there came a crashing noise on the edge of the clearing so loud that all of them, Harry, Hermione and the fifty or so centaurs filling the clearing, looked around. [OotP ch. #33; p. 667]
Harry wound his hand tightly into the mane of the nearest Thestral, placed a foot on a stump nearby and scrambled clumsily on to the horse's silken back. [cut] For a moment Harry's Thestral did nothing at all; then, with a sweeping movement that nearly unseated him, the wings on either side extended; the horse crouched slowly, then rocketed upwards so fast and so steeply that Harry had to clench his arms and legs tightly around the horse to avoid sliding backwards over its bony rump. He closed his eyes and pressed his face down into the horse's silky mane [OotP ch. #34; p. 674/675]
As he crossed the dark yard, the great, skeletal Thestral looked up, rustled its enormous bat-like wings, then resumed its grazing. [HBP ch. #05; p. 74]
'Not food or anythin'!' said Hagrid eagerly. 'He can get his own food, no problem. Birds an' deer an' stuff [OotP ch. #30; p. 610]
Gazing blearily around, Grawp reached out a hand the size of a beach umbrella, seized a bird's nest from the upper branches of a towering pine and turned it upside-down with a roar of apparent displeasure that there was no bird in it [OotP ch. #30; p. 613]
Harry was not sure whether or not it was his imagination, but he rather thought he saw a small cloud of birds erupting into the air over the tree tops in the distance, almost as though the tree in which they had been nesting had just been pulled up by the roots. [OotP ch. #30; p. 619]
The first thing they saw on entering Hagrid's cabin was Buckbeak, who was stretched out on top of Hagrid's patchwork quilt, his enormous wings folded tight to his body, enjoying a large plate of dead ferrets. [PoA ch. #14; p. 201]
Hagrid held up the limp rooster. 'Second one killed this term,' he explained. 'It's either foxes or a Blood-Suckin' Bugbear, an' I need the Headmaster's permission ter put a charm around the hen-coop.' [CoS ch. #11; p. 150]
There are also creatures which Hagrid mentions which are not specifically identified as living in the Forest, but which probably do, since it seems unlikely they are living on the lawn; foxes, for example, and stoats, and Blood-Sucking Bugbears (which I would guess is some sort of badger, unless it's a giant beetle larva big enough to do the same sort of damage as a fox). The dead ferrets which Hagrid feeds to Buckbeak also probably come from the Forest, although it seems unlikely Hagrid has been killing large numbers of domestic pets, and they are more probably polecats (ferrets being domesticated, tame polecats).
'There's nothin' that lives in the Forest that'll hurt yeh if yer with me or Fang,' [PS ch. #15; p. 183]
'Could a werewolf be killing the unicorns?' Harry asked. 'Not fast enough,' said Hagrid. [PS ch. #15; p. 183]
'There's summat in here that shouldn' be.' 'A werewolf?' Harry suggested. 'That wasn' no werewolf an' it wasn' no unicorn, neither,' said Hagrid grimly. [PS ch. #15; p. 184]
'Right,' said Ron [cut] 'Er – aren't there – aren't there supposed to be werewolves in the Forest?' [cut] Preferring not to answer that question, Harry said, 'There are good things in there, too. The centaurs are all right, and the unicorns.' [CoS ch. #15; p. 200]
[cut] 'big, blundering Hagrid, in trouble every other week, trying to raise werewolf cubs under his bed, sneaking off to the forbidden forest to wrestle trolls.' [CoS ch. #17; p. 230]
There are also rumours of werewolves in the Forest, but we don't know if these are true - except when Lupin is around. Hagrid tells the children that 'There's nothin' that lives in the Forest that'll hurt yeh if yer with me or Fang', but that's not firm evidence that there aren't werewolves: just that if there are, Hagrid believes they are on comparatively good terms with him. Or it's not full moon. Hagrid, after all, is saying this in the full knowledge that there are Acromantulas in the woods.
The possible presence of werewolves in the Forest is mentioned to Hagrid a couple of times in PS and in neither case does he suggest that there aren't werewolves there - but nor does he definitely confirm that there are. And of course, there might be no werewolves normally, and he might still consider that 'summat in here that shouldn' be' might be a were.
In any case, why would werewolves live in the Forest, since they are human most of the time? If there really are werewolves there, were they thrown over the wall and abandoned by their parents as children, and are living wild? More likely they are regular weres who come there looking for a safe place to transform, or who are hiding from Greyback's lot.
And there was Tom's accusation about Hagrid raising werewolf pups under his bed. Was there any truth or even feasibility to this? What would a werewolf pup be? Perhaps the offspring of a werewolf and a normal dog or wolf, or of two weres who mated whilst transformed. It could even be a mortal dog which has been bitten and infected.
If eyes hadn't been shining out of the deep, dark sockets, he might have been a corpse. The waxy skin was stretched so tightly over the bones of his face, it looked like a skull. His yellow teeth were bared in a grin. It was Sirius Black. [PoA ch. #17; p. 248]
'I was thin, very thin ... thin enough to slip through the bars ... I swam as a dog back to the mainland ... I journeyed north and slipped into the Hogwarts grounds as a dog ... I've been living in the Forest ever since ... [PoA ch. #20; p. 273]
'And I'd like to see the disguise that could fool those Dementors. They're guarding every single entrance to the grounds.' [PoA ch. #09; p. 123]
The Forest seems to be about four miles across, of which more anon, which I would have thought might be just about big enough to support the predators we see. The Acromantulas, being cold-blooded, probably don't eat very much; the Thestrals can fly so they can hunt where they please and the centaurs are probably vegetarian, if they have equine stomachs. Still, it's pushing it to have viable breeding populations of three large herbivores (deer, unicorns and centaurs), a large omnivore (Thestrals) and a very large carnivore (Acromantulas) in swuch a small area. It has been suggested that the Forbidden Forest is just an enclave on the edge of a much larger and less magical forest to which the centaurs, at least - being sentient and reclusive and able to make their own arrangements about not being seen by Muggles - may have access.
Hermione refers to "every single entrance to the grounds", which certainly means more than one and probably more than three. She's not including the tunnels in that (unless she's mistaken about them guarding every one), since Harry comes and goes through the tunnels freely, so the implication is that there are three or more ways into the grounds. We've got the main gates and the station path, and it's reasonable to speculate that there may be
There seems to be remarkably little in the way of small edible herbivores such as rabbits and squirrels: possibly the Acromantulas and the werewolves and the school's self-feeding owls have eaten them all. Not only do we not see them, but Sirius manages to live the best part of a year in the Forest as a dog and still end up as desperately thin as when he left Azkaban: either the Forest is remarkably short on suitable prey or he is a remarkably incompetent predator. They were moving into the very heart of the forest. [cut][cut] they had reached the rim of a vast hollow, a hollow which had been cleared of trees [cut][cut] The massive specimen that was carrying Harry made its way down the steep slope, towards a misty domed web in the very centre of the hollow [CoS ch. #15; p. 204] [cut] more giant spiders were climbing the side of the building, liberated from the Forbidden Forest into which the Death Eaters must have penetrated. [DH ch. #32; p. 513/514] [cut] Yaxley and Dolohov stepped out into a clearing that Harry knew had been the place where the monstrous Aragog had once lived. The remnants of his vast web were there still, [DH ch. #34; p. 562] Possibly Sirius really is an incompetent canine, and there are plenty of deer and rabbits and streams full of fish which we haven't been told about. But if food really is scarce, at least we are told that the Acromantulas are normally confined to the Forest, so they can't come out and snack on villagers, or on students so long as they obey the rules. In PoS, the Acromantulas occupy a domed nest in a hollow at the heart of the wood. By the time of the final battle of Hogwarts, though, the spiders have either moved on or been driven out, since only a "remnant" of Aragog's old nest remains. It may be that when Aragog dies his descendants abandon his house for ritual reasons, and build a new nest elsewhere. Return to contents-list Layout
[cut] more giant spiders were climbing the side of the building, liberated from the Forbidden Forest into which the Death Eaters must have penetrated. [DH ch. #32; p. 513/514]
[cut] Yaxley and Dolohov stepped out into a clearing that Harry knew had been the place where the monstrous Aragog had once lived. The remnants of his vast web were there still, [DH ch. #34; p. 562]
Possibly Sirius really is an incompetent canine, and there are plenty of deer and rabbits and streams full of fish which we haven't been told about. But if food really is scarce, at least we are told that the Acromantulas are normally confined to the Forest, so they can't come out and snack on villagers, or on students so long as they obey the rules.
In PoS, the Acromantulas occupy a domed nest in a hollow at the heart of the wood. By the time of the final battle of Hogwarts, though, the spiders have either moved on or been driven out, since only a "remnant" of Aragog's old nest remains. It may be that when Aragog dies his descendants abandon his house for ritual reasons, and build a new nest elsewhere.
As regards the layout of the Forbidden Forest, we've already seen, above, that there is a shadowy clearing, among densely-packed trees which include a tall beech, probably about a hundred yards into the Forest and accessible from a point which is visible from a position to the left of the castle's main doors - to the left as you face them, that is.
[We know Harry is so placed that he can see the side of the castle which faces the Forest - since we know the sun sets over the Forest, and he can see the setting sun reflecting from the castle windows. Yet, to get to the stretch of Forest where Snape is headed, Harry has to fly over part of the castle. This suggests that the broom shed, where Harry starts from, is tucked into the angle of the nort-west block, since we have other evidence that the north-west block projects from the castle towards the Forest. That places him somewhere to the left of the door as you face the castle.]
There may be a path, or at least a sort of a track in to this clearing, since Snape enters the woods at a run. Other than this, the books repeatedly mention a path into the woods near Hagrid's hut, and no other. It is probable, therefore, that either Snape's clearing is accessed via this path by Hagrid's hut or, if it has its own path, that path is insignificant and does not go deeper into the woods. If Harry indeed flies over the west wing in order to watch Snape enter the woods, that suggests that the clearing may have its own path, away from Hagrid's hut, which in turn suggests that the clearing may have some sort of regular use. It could be a popular love-nest, or perhaps Snape uses it to grow potion ingredients. The main path starts somewhere just beyond Hagrid's hut, so it is unlikely to be that which is meant.
In addition to Harry's airborne jaunt to spy on Snape, we are shown six trips into the Forest proper: the detention with Hagrid where they see Quirrelmort feeding on the dead unicorn in PS; the diplomatic mission to the Acromantulas in CoS; the Thestral-watching trip in OotP; the visit to Grawp in OotP; the frantic scramble at the end of OotP where they feed Umbridge to the centaurs and hitch a ride on the Thestrals, and Harry's walk to confront Voldemort at the old Acromantula encampment in DH.
He led them to the very edge of the Forest. Holding his lamp up high he pointed down a narrow, winding earth track that disappeared into the thick black trees. A light breeze lifted their hair as they looked into the Forest. [cut] The Forest was black and silent. A little way into it they reached a fork in the earth path and Harry, Hermione, and Hagrid took the left path while Malfoy, Neville and Fang took the right. They walked in silence, their eyes on the ground. Every now and then a ray of moonlight through the branches above lit a spot of silver-blue blood on the fallen leaves. [PS ch. #15; p. 183]
They walked past a mossy tree-stump. Harry could hear running water; there must be a stream somewhere close by. There were still spots of unicorn blood here and there along the winding path. [cut] Hagrid seized Harry and Hermione and hoisted them off the path behind a towering oak. He pulled out an arrow and fitted it into his crossbow, raising it, ready to fire. The three of them listened. Something was slithering over dead leaves nearby: [cut] after a few seconds, the sound faded away. [PS ch. #15; p. 183/184]
They walked more slowly, ears straining for the faintest sound. Suddenly, in a clearing ahead, something definitely moved. [cut] And into the clearing came - was it a man, or a horse? [PS ch. #15; p. 184]
They walked on through the dense, dark trees. [cut] They had just passed a bend in the path when Hermione grabbed Hagrid's arm. 'Hagrid! Look! Red sparks, the others are in trouble!' 'You two wait here!' Hagrid shouted. 'Stay on the path, I'll come back for yeh!' They heard him crashing away through the undergrowth and stood looking at each other, very scared, until they couldn't hear anything but the rustling of leaves around them. [PS ch. #15; p. 185/186]
'Right, we're changin' groups - Neville, you stay with me an' Hermione. Harry, you go with Fang an' this idiot.' [cut] So Harry set off into the heart of the Forest with Malfoy and Fang. They walked for nearly half an hour, deeper and deeper into the Forest, until the path became almost impossible to follow because the trees were so thick. Harry thought the blood seemed to be getting thicker. There were splashes on the roots of a tree, as though the poor creature had been thrashing around in pain close by. Harry could see a clearing ahead, through the tangled branches of an ancient oak. [PS ch. #15; p. 186]
And Firenze whisked around; with Harry clinging on as best he could they plunged off into the trees, leaving Ronan and Bane behind them. [cut] Firenze slowed to a walk, warned Harry to keep his head bowed in case of low-hanging branches [cut] They made their way through the trees in silence for so long that Harry thought Firenze didn't want to talk to him any more. They were passing through a particularly dense patch of trees [PS ch. #15; p. 188]
Hermione was running towards them down the path, Hagrid puffing along behind her. [PS ch. #15; p. 189]
When Harry, Hermione, Neville and Draco go with Hagrid and Fang to look for the injured unicorn in PS, they meet Hagrid somewhere midway between the castle and his cabin, and from there they go to the edge of the Forest and pick up a narrow earth track which winds away through thick black trees. They start down this track, and a little way along it they come to a fork.
Draco, Neville and Fang take the right fork, but we are not told what it leads to. Hagrid, Harry and Hermione take the left fork, which leads through an area of deciduous woods (leaves on the ground). It continues to be winding. After an unspecified but fairly long time it leads past a mossy stump, and there is a running stream somewhere nearby.
Just past the mossy stump, they have their first encounter with Quirrelmort, and Hagrid pulls them off the path and behind a towering oak. Again, this is a deciduous area, as there is a cover of dead leaves on the ground, thick enough to rustle.
Continuing slowly down the path, they come to a clearing where they meet two centaurs. Beyond that there are more dense, dark, deciduous trees (with rustling leaves). The path goes round a bend, just after which they are able - despite the dense trees - to see a flare of red sparks cast by Neville on the other path. Hagrid then sets out in the direction of the right-hand path, passing through undergrowth en route. From the sound of it they are probably now at least half a mile into the Forest.
Once the others have rejoined them, the groups re-assort and Harry, Draco and Fang head deeper into the Forest for nearly half an hour. Even if they are going at only half normal walking speed this must be over half a mile further in, so they are something over a mile in at the end. We are not told which path they are on - although they definitely are on a path. The fact that Hagrid tells Harry to "go with" Draco suggests that Hagrid stayed on the left path and Harry is now on the right, but on the other hand it seems more likely that it would be the party with Hagrid who cross the trackless wood from one path to the other, meaning that Harry and Draco stay where they now are, on the left path.
As they walk further in, the path becomes hard to follow because the trees are crowded so thickly. They see blood on the roots of a tree, then an ancient oak with tangled branches, through which they see another clearing (again, floored with dead leaves, so mainly deciduous wood) where they see the dead unicorn, and Quirrelmort.
Firenze then picks Harry up and takes him to rejoin Hagrid and Hermione, who are on a proper path open enough for Hagrid to walk it. They are very probably on the right-hand fork of the original path. In getting there, Firenze takes Harry through an area where the branches are low enough to be a danger to a mounted man, and through an especially dense patch of trees.
They listened. Some distance to their right, the something big was snapping branches as it carved a path through the trees. [cut] Then, to their right, came a sudden blaze of light, so bright in the darkness that both of them flung up their hands to shield their eyes. Fang yelped and tried to run, but got lodged in a tangle of thorns and yelped even louder. [cut] Harry blundered after Ron towards the light, stumbling and tripping, and a moment later they had emerged into a clearing. Mr Weasley's car was standing, empty, in the middle of a circle of thick trees under a roof of dense branches, its headlamps ablaze. As Ron walked, open-mouthed, towards it, it moved slowly towards him, exactly like a large, turquoise dog greeting its owner. [CoS ch. #15; p. 203]
Harry squinted around on the floodlit ground for signs of more spiders, but they had all scuttled away from the glare of the headlights. [cut] Ron didn't speak. [cut] His eyes were fixed on a point some ten feet above the forest floor [cut] Harry didn't even have time to turn around. There was a loud clicking noise and suddenly he felt something long and hairy seize him around the middle [cut] [cut] They were moving into the very heart of the forest. Harry could hear Fang fighting to free himself from a third monster, whining loudly, but Harry couldn't have yelled even if he had wanted to; he seemed to have left his voice back with the car in the clearing. He never knew how long he was in the creature's clutches; he only knew that the darkness suddenly lifted enough for him to see that the leaf-strewn ground was now swarming with spiders. Craning his neck sideways, he realised that they had reached the rim of a vast hollow, a hollow which had been cleared of trees, so that the stars shone brightly onto the worst scene he had ever clapped eyes on. Spiders. Not tiny spiders like those surging over the leaves below. Spiders the size of carthorses, eight-eyed, eight-legged, black, hairy, gigantic. The massive specimen that was carrying Harry made its way down the steep slope, towards a misty domed web in the very centre of the hollow, while its fellows closed in all around it, clicking their pincers excitedly at the sight of its load. [CoS ch. #15; p. 204]
And from the middle of the misty domed web, a spider the size of a small elephant emerged [CoS ch. #15; p. 205]
They sped up the slope, out of the hollow, and they were soon crashing through the forest, branches whipping the windows as the car wound its way cleverly through the widest gaps, following a path it obviously knew. [cut] They smashed their way through the undergrowth, Fang howling loudly in the back seat, and Harry saw the wing mirror snap off as they squeezed past a large oak. After ten noisy, rocky minutes, the trees thinned, and Harry could again see patches of sky. The car stopped so suddenly that they were nearly thrown into the windscreen. They had reached the edge of the Forest. Fang flung himself at the window in his anxiety to get out and when Harry opened the door, he shot off through the trees to Hagrid's house, tail between his legs. [CoS ch. #15; p. 207]
Harry went back into Hagrid's cabin to get the Invisibility Cloak. [cut] When Harry got outside again, he found Ron being violently sick in the pumpkin patch. [CoS ch. #15; p. 208]
When Harry and Ron follow the spiders, they enter the wood by a path which is some small distance from Hagrid's cabin and which they refer to as "the" path - so it may well be the one they used before. They enter it at a point near a large sycamore tree and an area of deciduous leaf-fall. They follow the path for about twenty minutes - just under a mile at a normal, casual walking speed, so between half a mile and a mile, depending on how fast they are going, but probably closer to the half mile since they are walking behind small spiders.
They then leave the path (we're not told in which direction) and walk for what feels like half an hour - so is probably about another twenty minutes - first through an area of intrusive roots and broken stumps, then through low branches and brambles. They are going quite slowly, so probably not for more than another half mile (so all told they have probably come about a mile). Towards the end of that time that the ground underfoot is beginning to slope downward, although the tree-cover is still as dense.
On this downward slope, they find themselves in an area where there are tangled thorns (so the trees have probably thinned out a bit, to allow enough light in for thorns to grow), branches lower than the roof of a Ford Anglia, and a sort of circular amphitheatre of trees - not quite a clearing because it is roofed over with branches, but a bare circle big enough to hold a Ford Anglia and still allow room for it to move a bit, and surrounded by thick trees.
Into this clearing comes a giant spider, its jaws about ten feet above the ground. The spiders carry Harry, Ron and Fang an unknown distance into the heart of the Forest, presumably still downslope, until they reach a great hollow which has been cleared of trees.
This hollow is steep-sided and big enough to hold a large number of carthorse-sized creatures without crowding them, so it is probably at least fifty yards across - probably bigger, since it's described as "vast". At the centre is a misty domed web big enough to hold Aragog, who is the size of a small elephant. The hollow should be fairly close to a water supply, in order to be a practicable base-camp for the spiders, but not so close that it floods - say about a hundred yards.
Harry, Ron and Fang smash their way out in the Ford Anglia, driving through undergrowth and past a large oak tree (deciduous woods again). It takes ten minutes to get to the edge of the Forest. We do not know how fast the car is travelling, nor how far the spiders carried the boys from the point where they picked them up: certainly it's not moving very fast for a car, since it is having to plough through underbrush and scrape past trees. However, it's evidently going faster than the Acromantulas can chase it; so say fifteen miles an hour. If it kept that up, that would mean that in ten minutes it travelled about two and a half miles, and the Acromantulas carried Harry, Ron and Fang about a mile and a quarter from where they picked them up, which seems reasonable - assuming that they travelled in a straight line in the first place, but as they were following the spiders, and the spiders were heading for Aragog, they probably did.
However, on the occasion of his final trip into the Forest to confront Voldemort, q.v., Harry has time to descend from the Headmaster's office to the Entrance Hall, cross to the start of the path by Hagrid's hut (some 320 yards from the main doors) and walk to Aragog's nest in just over half an hour, in the dark and for much of the time off the path, and walking over twisted tree-roots. Even assuming that the spirits helped him to find a clear route this is pushing it, and we must assume that the spiders in fact did not go straight to Aragog's nest, nor the car return straight from it to the edge of the Forest. In order for Harry to have had time to do all that in an hour, the lair cannot be much more than a mile and a half into the woods, and really should be less than that - even one and a third miles, which is the distance one would travel in half an hour at normal walking speed on clear paths, is pushing it. Either Acromantulas are slower than eight miles an hour, or the car accelerated to shake them off and then slowed down.
The Acromantula nest was said to be in the heart of the Forest, which is slightly problematic if it's only one and a third miles from Hogwarts. In order to support all the wildlife we see, and indeed to count as a forest rather than just a large wood, the Forbidden Forest needs to be three or four miles across. Perhaps the Acromantulas' hollow is in the heart of the Forest in the sense that it is in the dense inner area as opposed to the outskirts, rather than being near the middle. Hagrid's hut loomed out of the darkness. There were no lights, [cut] He moved on, and now he reached the edge of the Forest, and he stopped. [DH ch. #34; p. 559] The fact that when they get to the edge of the Forest Ron ends up in Hagrid's back garden tends to confirm that the entrance to the path is very close to Hagrid's hut and slightly past it as you come from the castle, as we see in DH. At the end of OotP when they take Umbridge to the centaurs, they are said to be following the same path as the one that leads to the Acromantulas (see below). They take that path to the point at which they mount the Thestrals and the Thestrals then fly them out over the castle and then over the village, heading for London which must - wherever they are in Scotland - be broadly to the south-east. The castle is about north-east of the village (see map) so in order to pass over first the castle and then even the easternmost past of the village they have to have been a little off-course (perhaps because there were moutains in the way), but the most likely starting-point would be somewhere north of the castle, in the Forest. So the Thestrals' launching-point, which is en route to the Acromantulas, is north of the castle, which means that if the path they set out on was the same as the forked path in PS, they must have taken the right-hand fork to head for Aragog. It makes sense that the Acromantula nest would tend to be to the right and north because the forest slopes down in that direction - and that's the direction away from the mountain which is near Hogsmeade. It was with a certain amount of apprehension that Harry, Ron and Hermione headed down to Hagrid's on Tuesday [cut] [cut] they struggled through the snow towards Hagrid, who stood waiting for them on the edge of the Forest. [OotP ch. #21; p. 391] 'We're workin' in here today!' Hagrid called happily to the approaching students, jerking his head back at the dark trees behind him. 'Bit more sheltered! Anyway, they prefer the dark.' [cut] He turned and strode straight into the Forest. [OotP ch. #21; p. 392] They walked for about ten minutes until they reached a place where the trees stood so closely together that it was as dark as twilight and there was no snow at all on the ground. With a grunt, Hagrid deposited his half a cow on the ground, stepped back and turned to face his class, most of whom were creeping from tree to tree towards him, peering around nervously as though expecting to be set upon at any moment. [cut] Hagrid gave the shrieking cry again. A minute passed in which the class continued to peer nervously over their shoulders and around trees for a first glimpse of whatever it was that was coming. And then, as Hagrid shook his hair back for a third time and expanded his enormous chest, Harry nudged Ron and pointed into the black space between two gnarled yew trees. A pair of blank, white, shining eyes were growing larger through the gloom and a moment later the dragonish face, neck and skeletal body of a great, black winged horse emerged from the darkness. [OotP ch. #21; p. 392/393] 'Ignore them, just ignore them,' intoned Hermione, pulling out her wand and performing the charm to produce hot air again, so that she could melt them an easier path through the untouched snow between them and the greenhouses. [OotP ch. #21; p. 398] They were soon a long way past the clearing where Hagrid had shown them the Thestrals [OotP ch. #30; p. 606] When Hagrid takes them to see the Thestrals, they enter the Forest at an unspecified point probably close to Hagrid's cabin (because they usually head for his cabin for Care of Magical Creatures, and in so doing they see him at the edge of the Forest). We are not told what route they take. However, later, at the end of OotP when they ride the Thestrals, the Thestrals burst out of the woods and then pass over the castle and then the village (which is more or less south-west of the castle), heading broadly south-east towards London. That suggests that the place where they mount the Thestrals is broadly north of the castle. That means that standing facing into the Forest, at a point between the castle and Hagrid's cabin, the Thestrals' launching-point is somewhere to the right. When they go to feed Umbridge to the centaurs, and to ride the Thestrals, we are told (see below) that the route they are following is the same route Harry and Ron took when they met the Acromantulas. So the Acromantulas are somewhere to the right. We are also told that this not the route they took when they went to visit Grawp. The road they took to visit Grawp (see below) takes them past the point where Hagrid first showed them the Thestrals. Ergo, the place where Hagrid first showed them the Thestrals is more to the left (or much more to the right - but that would probably take them right up against the boundary wall). To get to the place where Hagrid shows them the Thestrals they walk for ten minutes - at normal walking speed that would be just under half a mile, but as they are going through woodland, even if on a clear path, it's probably rather less than that - say about 600 yards. They come to a place where the trees, including at least two gnarled yews, grow together very thickly. It is later referred back to as being a clearing, but it must be tiny and thickly-roofed, because the snow is unable to penetrate. Here they meet the Thestrals. On the way back, they walk across open snow to the greenhouses, and this is the only time that anyone is described as walking to the greenhouses and not specified as crossing the vegetable patch to get there. This taken by itself suggests that they indeed went some distance to the north to see the Thestrals, then came back by a different route and emerged in the grounds on the "back" side of the greenhouses. However, other evidence listed above suggests they went in the other direction, to the west, so perhaps JK just didn't mention the vegetable patch this time.
The fact that when they get to the edge of the Forest Ron ends up in Hagrid's back garden tends to confirm that the entrance to the path is very close to Hagrid's hut and slightly past it as you come from the castle, as we see in DH. At the end of OotP when they take Umbridge to the centaurs, they are said to be following the same path as the one that leads to the Acromantulas (see below). They take that path to the point at which they mount the Thestrals and the Thestrals then fly them out over the castle and then over the village, heading for London which must - wherever they are in Scotland - be broadly to the south-east. The castle is about north-east of the village (see map) so in order to pass over first the castle and then even the easternmost past of the village they have to have been a little off-course (perhaps because there were moutains in the way), but the most likely starting-point would be somewhere north of the castle, in the Forest. So the Thestrals' launching-point, which is en route to the Acromantulas, is north of the castle, which means that if the path they set out on was the same as the forked path in PS, they must have taken the right-hand fork to head for Aragog. It makes sense that the Acromantula nest would tend to be to the right and north because the forest slopes down in that direction - and that's the direction away from the mountain which is near Hogsmeade.
At the end of OotP when they take Umbridge to the centaurs, they are said to be following the same path as the one that leads to the Acromantulas (see below). They take that path to the point at which they mount the Thestrals and the Thestrals then fly them out over the castle and then over the village, heading for London which must - wherever they are in Scotland - be broadly to the south-east. The castle is about north-east of the village (see map) so in order to pass over first the castle and then even the easternmost past of the village they have to have been a little off-course (perhaps because there were moutains in the way), but the most likely starting-point would be somewhere north of the castle, in the Forest.
So the Thestrals' launching-point, which is en route to the Acromantulas, is north of the castle, which means that if the path they set out on was the same as the forked path in PS, they must have taken the right-hand fork to head for Aragog.
It makes sense that the Acromantula nest would tend to be to the right and north because the forest slopes down in that direction - and that's the direction away from the mountain which is near Hogsmeade.
'We're workin' in here today!' Hagrid called happily to the approaching students, jerking his head back at the dark trees behind him. 'Bit more sheltered! Anyway, they prefer the dark.' [cut] He turned and strode straight into the Forest. [OotP ch. #21; p. 392]
They walked for about ten minutes until they reached a place where the trees stood so closely together that it was as dark as twilight and there was no snow at all on the ground. With a grunt, Hagrid deposited his half a cow on the ground, stepped back and turned to face his class, most of whom were creeping from tree to tree towards him, peering around nervously as though expecting to be set upon at any moment. [cut] Hagrid gave the shrieking cry again. A minute passed in which the class continued to peer nervously over their shoulders and around trees for a first glimpse of whatever it was that was coming. And then, as Hagrid shook his hair back for a third time and expanded his enormous chest, Harry nudged Ron and pointed into the black space between two gnarled yew trees. A pair of blank, white, shining eyes were growing larger through the gloom and a moment later the dragonish face, neck and skeletal body of a great, black winged horse emerged from the darkness. [OotP ch. #21; p. 392/393]
'Ignore them, just ignore them,' intoned Hermione, pulling out her wand and performing the charm to produce hot air again, so that she could melt them an easier path through the untouched snow between them and the greenhouses. [OotP ch. #21; p. 398]
They were soon a long way past the clearing where Hagrid had shown them the Thestrals [OotP ch. #30; p. 606]
When Hagrid takes them to see the Thestrals, they enter the Forest at an unspecified point probably close to Hagrid's cabin (because they usually head for his cabin for Care of Magical Creatures, and in so doing they see him at the edge of the Forest).
We are not told what route they take. However, later, at the end of OotP when they ride the Thestrals, the Thestrals burst out of the woods and then pass over the castle and then the village (which is more or less south-west of the castle), heading broadly south-east towards London. That suggests that the place where they mount the Thestrals is broadly north of the castle. That means that standing facing into the Forest, at a point between the castle and Hagrid's cabin, the Thestrals' launching-point is somewhere to the right.
When they go to feed Umbridge to the centaurs, and to ride the Thestrals, we are told (see below) that the route they are following is the same route Harry and Ron took when they met the Acromantulas. So the Acromantulas are somewhere to the right. We are also told that this not the route they took when they went to visit Grawp. The road they took to visit Grawp (see below) takes them past the point where Hagrid first showed them the Thestrals. Ergo, the place where Hagrid first showed them the Thestrals is more to the left (or much more to the right - but that would probably take them right up against the boundary wall).
To get to the place where Hagrid shows them the Thestrals they walk for ten minutes - at normal walking speed that would be just under half a mile, but as they are going through woodland, even if on a clear path, it's probably rather less than that - say about 600 yards. They come to a place where the trees, including at least two gnarled yews, grow together very thickly. It is later referred back to as being a clearing, but it must be tiny and thickly-roofed, because the snow is unable to penetrate. Here they meet the Thestrals.
On the way back, they walk across open snow to the greenhouses, and this is the only time that anyone is described as walking to the greenhouses and not specified as crossing the vegetable patch to get there. This taken by itself suggests that they indeed went some distance to the north to see the Thestrals, then came back by a different route and emerged in the grounds on the "back" side of the greenhouses. However, other evidence listed above suggests they went in the other direction, to the west, so perhaps JK just didn't mention the vegetable patch this time.
[Hagrid] forged a little ahead, taking one stride for every three of theirs, so that they had great trouble keeping up with him. The path was becoming increasingly overgrown and the trees grew so closely together as they walked further and further into the Forest that it was as dark as dusk. They were soon a long way past the clearing where Hagrid had shown them the Thestrals, but Harry felt no sense of unease until Hagrid stepped unexpectedly off the path and began wending his way in and out of trees towards the dark heart of the Forest. 'Hagrid!' said Harry, fighting his way through thickly knotted brambles, over which Hagrid had stepped with ease, and remembering very vividly what had happened to him on the other occasion he had stepped off the Forest path. [cut] It was a great struggle to keep up with Hagrid, what with branches and thickets of thorn through which Hagrid marched as easily as if they were cobwebs, but which snagged Harry and Hermione's robes, frequently entangling them so severely that they had to stop for minutes at a time to free themselves. Harry's arms and legs were soon covered in small cuts and scratches. They were so deep in the Forest now that sometimes all Harry could see of Hagrid in the gloom was a massive dark shape ahead of him. Any sound seemed threatening in the muffled silence. The breaking of a twig echoed loudly and the tiniest movement, even though it might have been made by an innocent sparrow, caused Harry to peer through the gloom for a culprit. It occurred to him that he had never managed to get this far into the Forest without meeting some kind of creature [OotP ch. #30; p. 606]
[cut] 'jus' a little bit further through here ... watch yerselves, now, there's nettles ...' They walked on in silence for another fifteen minutes; Harry had opened his mouth to ask how much further they had to go when Hagrid threw out his right arm to signal that they should stop. 'Really easy' he said softly. 'Very quiet, now ...' They crept forwards and Harry saw that they were facing a large, smooth mound of earth nearly as tall as Hagrid that he thought, with a jolt of dread, was sure to be the lair of some enormous animal. Trees had been ripped up at the roots all around the mound, so that it stood on a bare patch of ground surrounded by heaps of trunks and boughs that formed a kind of fence or barricade, behind which Harry, Hermione and Hagrid now stood. [OotP ch. #30; p. 608]
The trees to which the other ends of the ropes around Grawp's wrists and ankles were attached creaked ominously. He was, as Hagrid had said, at least sixteen feet tall. Gazing blearily around, Grawp reached out a hand the size of a beach umbrella, seized a bird's nest from the upper branches of a towering pine and turned it upside-down with a roar of apparent displeasure that there was no bird in it [cut] [cut] He had now seized the top of the pine tree and was pulling it towards him [cut] The giant let go of the top of the tree, which swayed alarmingly and deluged Hagrid with a rain of pine needles, and looked down. [OotP ch. #30; p. 612/613]
[cut] Harry and Hermione were struggling through a patch of thick knotgrass behind him. [cut] A man's naked torso seemed for an instant to be floating towards them through the dappled green half-light [cut] The trees behind the centaur rustled and four or five more centaurs emerged behind him. [OotP ch. #30; p. 614/615]
'Hagrid,' said Hermione breathlessly, skirting the patch of nettles they had passed on their way there, 'if the centaurs don't want humans in the Forest, it doesn't really look as though Harry and I will be able –' [OotP ch. #30; p. 616]
At last they rejoined the path and, after another ten minutes, the trees began to thin; they were able to see patches of clear blue sky again and, in the distance, the definite sounds of cheering and shouting. 'Was that another goal?' asked Hagrid, pausing in the shelter of the trees as the Quidditch stadium came into view. 'Or d'yeh reckon the match is over?' 'I don't know,' said Hermione miserably. Harry saw that she looked much the worse for wear; her hair was full of twigs and leaves, her robes were ripped in several places and there were numerous scratches on her face and arms. He knew he must look little better. 'I reckon it's over, yeh know!' said Hagrid, still squinting towards the stadium. 'Look – there's people comin' out already' [OotP ch. #30; p. 617]
They climbed the steps together. At the front doors both instinctively looked back at the Forbidden Forest. Harry was not sure whether or not it was his imagination, but he rather thought he saw a small cloud of birds erupting into the air over the tree tops in the distance, almost as though the tree in which they had been nesting had just been pulled up by the roots. [OotP ch. #30; p. 619]
'Well, he has,' said Hermione firmly. 'Grawp's about sixteen feet tall, enjoys ripping up twenty-foot pine trees, and knows me,' she snorted, 'as Hermy.' [OotP ch. #31; p. 622]
When they go to visit Grawp, they enter the wood at a point close to Hagrid's cabin, which they pass on the left. They are walking down a path, which appears to be the same one they went down when they visited the Thestrals. We know that the path which leads to the yew trees where they met the Thestrals is not the path which leads to the Acromantulas; and that the path that leads to the Acromantulas passes through an area north of the castle, where they will later mount the Thestrals. That path leads to the right: so if they are following the original path from PS, the one with the fork in it, the path that leads to Grawp must be the one that goes left.
Quite rapidly, they come on protruding roots and low-slung branches (low enough to obstruct Hagrid, anyway). They pass the Thestrals' clearing with the yew trees, and go a long way past it. As they travel, there is undergrowth invading the path and the trees grow very close together.
A long way past the Thestrals' clearing, they veer off from the path towards the heart of the Forest (which tells us that the path to the Thestrals does not point straight at the Forest's heart). They are at once in an area of brambles and perhaps other thorns which impede their progress. Although they are said to be travelling into the Forest's "dark heart", the presence of so much undergrowth actually means the leaf canopy must be thin enough to let light through. They nevertheless seem to be moving into an area where it is so dark they can hardly even see Hagrid.
They come to an area where there are nettles, which again implies light is getting through at some point. [Could it be that the Forest is in the shadow of a mountain at this time of day, but gets light at some other time? Unlikely: it's late morning.] Then they walk on for fifteen minutes - probably about half a mile, or a little under since they've left the path. Again, maybe 600 yards.
Here they come to an apparently artificial clearing where Grawp is shackled, surrounded by small pine trees. They must be small ones, because a tiny twenty-foot specimen is described as "towering".
On the way back, they pass through an area of thick knotgrass which certainly is getting light, described as "dappled green half-light". There is room here for about six centaurs, as well as Hagrid's party. This is definitely more or less on the same route they took going in, because shortly afterwards they pass the same nettles they passed before.
From the point at which they rejoin the path, it takes them ten minutes (again, 600 yards or so) to be in an area where the overhead cover is patchy and they can hear sounds from the Quidditch pitch. This doesn't make sense really, because the overgrown bit of path where they branched off should be about 950 yards (over half a mile) past the Thestral clearing, which was already in deep, dense woods. Presumbly then they rejoined the path about 400 yards nearer the edge of the Forest than they left it.
Following the path, they reach the edge of the woods at a point at which it is possible to see the stadium.
Looking back from the front steps of the castle, Harry can (probably) see the area where Grawp is confined, and it is close enough to enable them to make out birds, at least as a sort of cloud of tiny specks. That need not be very close: there is plenty of evidence (e.g. his recognising his own resemblance to James, across the lake by moonlight, and his looking out from Gryffindor Tower and identifying Crookshanks at the edge of the forest in the pre-dawn half-light, both in PoA) that Harry is very long- not short-sighted.
The fact that Hagrid's party left the path and headed "towards the dark heart of the Forest" for well over fifteen minutes before reaching Grawp, and yet Harry can see, or at least thinks he can see, Grawp's location from the front steps of the castle, means that a substantial chunk of the Forest must be broadly in front of the castle. Grawp's position (or the point which Harry is looking at and thinks is Grawp's position) can't be out to the left, because that way lies the edge of the Forest and the village; but neither can it be very far to the right, because the projecting west wing of the castle cuts off the line of sight.
They walked on for what seemed a long time, until they were once again so deep into the Forest that the dense tree canopy blocked out all light. Harry had the feeling he had had before in the Forest, one of being watched by unseen eyes. 'How much further?' demanded Umbridge angrily from behind him. 'Not far now!' shouted Hermione, as they emerged into a dim, dank clearing. 'Just a little bit –' [OotP ch. #33; p. 664]
But they did not hear what else centaurs were, for at that moment there came a crashing noise on the edge of the clearing so loud that all of them, Harry, Hermione and the fifty or so centaurs filling the clearing, looked around. Harry's centaur let him fall to the ground again as his hands flew to his bow and quiver of arrows. Hermione had been dropped, too, and Harry hurried towards her as two thick tree trunks parted ominously and the monstrous form of Grawp the giant appeared in the gap. The centaurs nearest him backed into those behind; the clearing was now a forest of bows and arrows waiting to be fired, all pointing upwards at the enormous greyish face now looming over them from just beneath the thick canopy of branches. Grawp's lopsided mouth was gaping stupidly; they could see his bricklike yellow teeth glimmering in the half-light [OotP ch. #33; p. 667]
Harry wound his hand tightly into the mane of the nearest Thestral, placed a foot on a stump nearby and scrambled clumsily on to the horse's silken back. [cut] For a moment Harry's Thestral did nothing at all; then, with a sweeping movement that nearly unseated him, the wings on either side extended; the horse crouched slowly, then rocketed upwards so fast and so steeply that Harry had to clench his arms and legs tightly around the horse to avoid sliding backwards over its bony rump. He closed his eyes and pressed his face down into the horse's silky mane as they burst through the topmost branches of the trees and soared out into a blood-red sunset. Harry did not think he had ever moved so fast: the Thestral streaked over the castle [cut] They were over the Hogwarts grounds, they had passed Hogsmeade [OotP ch. #34; p. 674/675]
Their next trip into the Forest is when Harry and Hermione lure Umbridge into the woods. They are going by the same route which Harry and Ron took to the Acromantulas, which is probably to the right.
Moving fast, they come quite rapidly to brambles and undergrowth (and a fallen sapling), and then continue on for a long time until they are again in an area of dense tree-cover. It is not clear whether they are sticking to the path or not: if not, they probably left it early on, at the point where they got mixed up with the brambles.
They come to a dim, dank clearing which is large enough to hold fifty centaurs in addition to themselves - and does so. At that point, they are joined by Grawp. The trees around the clearing are close enough together that he has to lever two apart to get through. The clearing has at least some thick-trunked trees around it, at least one stump of a size suitable for use as a mounting-block, and the branches mostly start about eighteen feet above the ground (just over the head of Grawp, who has been established as at least sixteen feet tall).
Harry and Hermione run into the trees at the edge of the clearing, where there is a tree-stump. Here they are joined by Ron, Ginny, Luna and Neville - and the Thestrals. Taking off on Thestral-back they pass over the castle, then the village on their way south-east, so the clearing is broadly north of the castle.
He looked down at the battered gold watch he had received on his seventeenth birthday. Nearly half of the hour allotted by Voldemort for his surrender had elapsed. [DH ch. #34; p. 556]
He moved down the steps and out into the darkness. [DH ch. #34; p. 557]
Hagrid’s hut loomed out of the darkness. [cut] He moved on, and now he reached the edge of the Forest [DH ch. #34; p. 559]
Two figures emerged from behind a nearby tree: their wands flared, and Harry saw Yaxley and Dolohov peering into the darkness,[cut] 'Time's nearly up. Potter's had his hour. He's not coming.' [cut] [Yaxley] and Dolohov turned and walked deeper into the Forest. Harry followed them, knowing that they would lead him exactly where he wanted to go. [cut] They had travelled on mere minutes when Harry saw light ahead, and Yaxley and Dolohov stepped out into a clearing that Harry knew had been the place where the monstrous Aragog had once lived. The remnants of his vast web were there still, [DH ch. #34; p. 562]
'I was, it seems ... mistaken,' said Voldemort. 'You weren't.' [DH ch. #34; p. 563]
[cut] Hagrid stumbled forwards, forcing his way through the close-growing trees, back through the Forest. Branches caught at Harry's hair and robes [cut][cut] The victorious procession marched on towards the open ground, and after a while Harry could tell, by the lightening of the darkness through his closed eyelids, that the trees were beginning to thin. [cut][cut] Harry wondered how many centaurs were watching their procession pass; [cut] A little later, Harry sensed, by a freshening of the air, that they had reached the edge of the Forest. [DH ch. #36; p. 582/583]
He could see, even through his closed lids, the reddish glow that meant light streamed upon him from the Entrance Hall. [DH ch. #36; p. 584]
The final time we follow the viewpoint of a character entering the Forest is when Harry walks to what he thinks will be his death in confrontation with Voldemort. Voldemort is camping at the site of Aragog's old nest, so Harry's journey takes him to the same place he went in CoS, although not necessarily by the same route.
Leaving the castle by the front steps, Harry passes by Hagrid's hut in order to enter the Forest. It's not clear how Harry knows where to go to, since Riddle simply says to meet him "in the Forbidden Forest" and it's a big place. It could be that Harry is following the prompting of his mental link with Voldemort. But since he enters the Forest at a point nowhere near Voldemort, and since almost every time we see anybody enter the Forest (except for Snape when he met Quirrell, and Hagrid when he fetched the Hipogriffs) they start off from the same point near Hagrid's hut, it may also be that even the fringes of the Forest are fairly impassable and there is only the one major path into it, starting near Hagrid's house. Harry knows this and he assumes that Tom will too, and that when Tom says "meet me in the Forbidden Forest", he will intend Harry to come in by that path.
At the very edge of the Forest, before entering it, he stops to use the Resurrection Stone. He then walks for an unkown distance "deeper and deeper into the Forest", accompanied by the spirits he has summoned, until he meets with Yaxley and Dolohov. He then follows them still deeper, but in "mere minutes" - so probably not much over five minutes at most - they reach Aragog's old lair.
Harry must have some instict, communicated from Tom, to tell him where to go, since it's a fairly big forest, and we saw before that you don't just follow the path to get to Aragog's lair.
After Harry's pseudo-death and undeath, the Death Eaters march back to the castle with Hagrid in the lead. The trees become gradually more wide-set as they go, and they emerge onto the lawn right in front of the main entrance of the castle.
'I shall wait for one hour in the Forbidden Forest. If, at the end of that time, you have not come to me,' [DH ch. #33; p. 529]
He moved down the steps and out into the darkness. It was nearly four in the morning [DH ch. #34; p. 557]
And he set off. The Dementors' chill did not overcome him; he passed through it with his companions, and they acted like Patronuses to him, and together they marched through the old trees that grew closely together, their branches tangled, their roots gnarled and twisted underfoot. Harry clutched the Cloak tightly around him in the darkness, travelling deeper and deeper into the Forest, with no idea where exactly Voldemort was, but sure that he would find him. [DH ch. #34; p. 561]
Yaxley looked down at his watch. 'Time's nearly up. Potter's had his hour. He's not coming.' [cut] He and Dolohov turned and walked deeper into the Forest. Harry followed them, [cut] They had travelled on mere minutes when Harry saw light ahead, and Yaxley and Dolohov stepped out into a clearing that Harry knew had been the place where the monstrous Aragog had once lived. [DH ch. #34; p. 562]
He had expected to hear cheers of triumph and jubilation at his death, but instead hurried footsteps, whispers, and solicitous murmurs filled the air. 'My Lord ... my Lord ...' [DH ch. #36; p. 580]
'I killed Severus Snape three hours ago,' [DH ch. #36; p. 594]
A red-gold glow burst suddenly across the enchanted sky above them, as an edge of dazzling sun appeared over the sill of the nearest window. The light hit both of their faces at the same time, so that Voldemort's was suddenly a flaming blur. [DH ch. #36; p. 595]
At the point at which he has just finished viewing Snape's memories, Harry has used up about twenty-five minutes of the hour which Voldemort gave him (which doesn't make any sense, given that he had to crawl the length of the tunnel from the Shack, but that's another story). He then descends all the way back down through the castle, which has to take at least some minutes, and goes to the edge of the Forest, another few minutes, especially in the dark. So from Voldemort's announcement that Harry has an hour, to the point at which Harry summons the spirits at the edge of the Forest, thirty to thirty-five minutes must have elapsed. The time is now a little before 4am - if we say 3:50am, that tells us that Snape died (or whatever) at about 3:20am.
When Harry meets up with Dolohov and Yaxley in the woods, his hour is almost up, and we are told that it then takes only "mere minutes", which sounds like probably not more than five minutes, to reach Aragog's lair. So from the time Tom gave Harry an hour until his reaching Aragog's lair took about sixty-five minutes, and only about thirty minutes of that time was spent in walking from the edge of the Forest to Aragog's lair. Unless the spirits who accompanied him somehow bent time for Harry, the distance to Aragog's lair cannot be all that far. Harry can't have gone more than a mile and a half and probably somewhat less, especially considering that the Forest has thick undergrowth and that he left the path partway through the journey (there are roots underfoot).
There then follows Harry's death scene, and his astral conversation with Dumbledore, which could have taken an hour, or no time at all. It probably only took a few minutes, because Tom collapsed, probably at the point at which he fired at Harry and killed his own Horcrux, and when Harry woke the Death Eaters were just becoming anxious about their master: not panicking because he'd been unconscious for an hour.
Then there's a bit of discussion about whether Harry is dead and what to do about it, and then they walk back through the Forest, ending up on the lawn in front of the castle. As they go, dawn must be breaking, or the lights from the castle must be very bright indeed, because there is enough light for Harry to tell, through his closed eyelids and over and above whatever Lumos spells the Death Eaters may be using, that the trees are getting further apart.
Then there is a considerable battle and a long, verbose confrontation between Harry and Voldemort, towards the end of which Voldemort says that it is three hours since he killed Snape, so we know it is now just after 6am. Shortly afterwards Voldemort is killed, and just at that point the sun clears the horizon. Normally in Scotland in early May the sunrise would be at about 5:30am British Summer Time, but Hogwarts is surrounded by mountains and they must have delayed the sunrise by around forty minutes, which is reasonable.
So, from the point at which Voldemort tried to kill Harry to the point at which Harry killed him was a fraction over two hours. The massed Death Eaters probably move more slowly through the Forest than Harry and the ghosts, so if the dying/undying and the discussion afterwards took fifteen minutes and the journey back through the Forest took thirty-five, that leaves an hour and twenty minutes for the fighting. That seems rather a long time for the amount of fighting we see. It also requires the sky to have been lightening significantly well over an hour before dawn.
Perhaps we can assume they took longer than that to walk through the Forest. Hagrid is large, he can't go everywhere that Harry and the ghosts could go, so unless he wanted to just smash down the trees, he may have had to go by way of an established path which did not run straight: perhaps following the same winding path used by the flying Ford Anglia when it smashed its way out of Aragog's hollow. He must have had an established path for visiting Aragog. Hagrid himself has long legs and can walk fast, but he is forced to go at the pace of the Death Eaters. If we say that the straight-line journey took Harry thirty minutes and the winding journey back took twice as long, that brings the time spent on the battle down to just under an hour, which is more feasible.
There's still a problem with the lightening sky, though. From an article entitled "Wake up to the dawn chorus" by Robert Burton, posted on the telegraph.co.uk website: "The first notes are heard an hour or so before dawn, when there is still no hint of sunrise and the eyes can barely make out the silhouettes of the trees." So however we look at it we must conclude that it wasn't sunlight Harry was seeing: either the moon was immensely bright, or what shone through the trees was the light of the castle burning.
The Forbidden Forest is mainly deciduous with an admixture of conifers, including at least one stand of pine-trees. It is probably about four miles across, at least in the south/north direction. Its extent to the north-west is constrained by the presence of a mountain in that direction but it is probably about two miles across on a south-east to north-west axis. We know this because while standing on the front steps of the castle, which faces somewhat north of west, with the view to the extreme right cut off by the protruding west wing of the building, it is possible to see an area deemed to be in the heart of the forest.
About a hundred yards in from the edge, in an area accessible from a point visible from the left of the castle doors, there is a shadowy clearing surrounded by densely-packed trees, including a tall beech. This clearing is accessed from a path: it is not clear whether this is the same path which starts near Hagrid's cabin (see below), but if it is not then it probably ends at the clearing.
There is a narrow, winding earth-floored path which leads into the Forest, passing through thick black trees. This path is probably the only significant clear path penetrating the deep Forest anywhere near the school. It starts by a tall sycamore tree, at a point which is just past Hagrid's cabin as you come from the castle, is close to the cabin, is visible as you come from the castle and which commands a view of the Quidditch pitch.
A little way into the Forest the path forks. The left fork winds about, so bits of it point in different directions, but overall it leads away at an angle which does not point directly towards the heart of the Forest, at least for the first mile or so, and this is probably so with the right fork as well.
The left fork winds away through an area of deciduous woods, and quite rapidly comes to an area of protruding roots and fairly low-slung branches (low enough to obstruct Hagrid, anyway). After a fairly long time it leads past a mossy stump, still among deciduous trees, at which point there is a running stream within earshot, presumably leading either to or from the lake. Just past the mossy stump there is a towering oak at the side of the path.
A fairly short way further along the path, at a point probably about 600 yards into the woods, there is a tiny, thick-roofed clearing where the trees - including at least two gnarled yews - grow together very thickly. Here they meet two centaurs in PS, and Hagrid shows them the Thestrals in OotP. Beyond this there are more dense, dark, deciduous trees. At least half a mile into the Forest, maybe more, the path goes round a bend. This bend may tend back towards the right-hand path, since from just past here Harry and Hermione can see the sparks from Neville's wand on the other path, suggesting that they are both fairly close to the other path and facing towards it. The left path from this point on is carrying them broadly towards the heart of the Forest, or certainly not away from it, otherwise Hagrid wouldn't use this path to get to Grawp when he is staying somewhere towards the centre of the woods.
Continuing on down the left path, by the time you are something over a half a mile past the clearing the path is hard to follow, because the trees are so thickly crowded and (at least by OotP) undergrowth is invading the path. At this point there is another clearing among deciduous trees, with an ancient oak with tangled branches standing on the side of the clearing you are approaching from.
If you leave the path in this overgrown area and head towards the heart of the Forest, you come at once into an area of brambles and perhaps other thorns. The area is described as leading into the Forest's "dark heart" but there must surely be some light getting through to support the undergrowth, unless the Forest is infested with magic thorns which grow in the dark.
You come to an area so dark even Hagrid is obscured, then to nettles, which implies the cover has opened out again, then through an area of thick knotgrass which is certainly open enough for there to be "dappled green half-light", and for six centaurs to fit in comfortably..
About 600 yards after leaving the path, there is an area of pine-trees, surrounding an artificial clearing where Grawp was confined. Coming back, they branched off their original route somewhere after the nettles, and rejoined the path about 400 yards nearer the edge of the Forest than where they first left it.
If instead you take the right-hand path at the fork, you come quite rapidly to brambles and undergrowth (at least by OotP you do), which suggests the wood is quite open in this direction. After a fairly long time you come to dense tree-cover, then to a dim, dank clearing big enough to hold fifty centaurs, and lying more or less north of the castle. We don't know what the trees are but they grow close together, and there is a stump just outside the clearing.
If you break away from this path about half a mile in, and head roughly towards the centre of the Forest, you come first to an area of intrusive roots and broken stumps, then to low branches and brambles. Another half a mile in, the ground begins to slope downwards noticeably, although the tree-cover is still as dense.
On this downward slope you pass through tangled thorns and past trees with branches lower than the roof of a Ford Anglia, and find a sort of circular amphitheatre: not quite a clearing because it is fully roofed-over with branches, but big enough to hold a small car and, later, a ten-foot-tall spider, and surrounded by thick trees.
Continuing downslope for probably a bit under half a mile, until you are about one and a third miles in a straightish line from the edge of the Forest, you come to a sort of hollow or crater, steep-sided, cleared of trees and at least fifty yards across and probably bigger. At the centre is a misty dome made of spiders' web, and big enough to house a small elephant.
There is undergrowth between the left and right-hand paths when you are a bit over half a mile into the woods. When you are over a mile in, the area between the two paths includes branches low enough to be a danger to a mounted man, and an especially dense patch of trees. A more or less direct line from the Acromantula nest back to near the start of the path takes you through undergrowth and past a large oak tree.
I have shown the map twice: once in an unlabelled overview version (below) which is displayed at a small enough size that you can see the whole map at a glance, in order to form an impression of the whole area, and then again in a labelled version which is at too high a magnification to fit on the screen, and has to be scrolled through. Because the map files are so large, even as .gifs, that having two of them on the same page my screw up your browser, I have placed the labelled map in a separate window until I think of a better way of doing this. The rectangles which you can see superimposed on the smaller, unlabelled map show the positions of the Hogwarts grounds and Hogsmeade maps.
Apart from the overall scale of the forest, and the position of the mountains, everything which lies north and north-west of Aragog's nest is just a "for instance", and within reason you can stick in anything you like without conflicting with canon. As discussed in the section on the setting of Hogwarts there are mountains broadly to the north-west, south-west and east of the castle, but apart from the one which lies nor' nor' west of Hogsmeade, where Sirius's cave was, and whose position is fixed, we do not know how far away the others are, except that they are reasonably close. Water flows from the mountains down into the lake, from the lake north and down through the forest and west through an underground channel which leads towards the village, and from the mountains directly into a system of streams which link to this overflow from the lake.
On the assumption that Hogwarts means "the howe of Arthur" and Hogsmeade means "the middle howe", I have included three howes or prehistoric mounds: one within the castle grounds just north of the greenhouses; one (the middle one, in Hogsmeade) which the Shrieking Shack stands on; and one about a mile and a half west of the village, at the foot of the mountain. These are only tenuously supported by canon.
Note that some fine details such as the boundary wall, footpaths and streams have been shown wider than scale because otherwise they would be so fine they would barely show up.
