I’ve long known that this structure would get at least one post to itself. It’s big, and so rich with detail! It’s also a weird throwback for me – the first render I did for this project was of the astronomy tower. Or at least, a simple proof of concept. Funnily enough, I never seem to have shared that render, so here it is in all its glory:

Beautiful, I know. 😉
Anyway, as you may know, the original Hogwarts featured the Defense Against the Dark Arts tower – so named by fans because a pullback in GOF implies that Moody’s office is in there. This structure moved but remained fundamentally unchanged all the way until HBP, at which point it was removed, redesigned, and reincarnated as the taller, fancier astronomy tower, which sits where the Dark Tower sat for years 3–5.
From the beginning, the books describe this tower as the castle’s tallest, located very close to the main entrance. The top has crenellated ramparts and a door to a spiral staircase. That’s about all we get. Since the tower was never featured in the first five films, its location, appearance, and even its existence weren’t established in the film canon. But all that had to change in HBP. The filmmakers needed an iconic tower from which a certain somebody could fall in the film’s climax.
As described in my recent blueprint appreciation post, we have some great elevations, sections, and plans for the final design:

It was thus tempting to just build based on these, but I decided to still assemble other references as usual. I was glad I did, because there are details visible in real life that aren’t in those drawings. I even found a few spots where they added extra windows or whatnot. Another complication is that the tower was created at 1:24 and 1:10 scales, plus (I suspect) an even larger miniature or CG asset for the nighttime shot that ascends past Ron, Lavender, and Draco. (That last version has a different design that I’ll ignore.) And then of course there was the full-scale set. I decided to aim for roughly the amount of detail on the main 1:24 miniature, while still paying attention to the others.
Anyway, I captured part of the process in this time lapse:
Or if you just want to look through some renders, enjoy these!
Still more work to do, but it’s a good start!
One of the most perplexing things about this tower is how its little sub-towers change depending on the shot – sometimes it has 2 on the flat side, sometimes 1.
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Are there any shots other than the one that ascends past Ron and Lavender (and then Malfoy) that show two? That’s the only one I can think of. That shot also changes the windows, gets rid of the big front telescope, and moves the whole tower to the other side of the Transfiguration courtyard. Plus it could be argued that Ron and Lavender are supposed to be in Gryffindor Tower. So I think of that shot as being more impressionistic than literal, and I don’t take its design as canon.
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I don’t recall in detail which differences it has in which shot. There is at least one shot where it has no turrents aside from the lookout, that is on the wiki and seems to be from a film scene, but I don’t know what scene it’s from by sight.
https://static.wikia.nocookie.net/harrypotter/images/d/d7/AstronomyTower.jpg/revision/latest?cb=20091009190800
I might not even have made it into the final film and only into promotional material, for all I know.
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Oh, that’s interesting. But yeah, that isn’t from any shot in the film. I’m guessing it was from a promotional image, like you said.
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Also I never noticed until now that the tower physically moved for the pan scene with Ron and Lavender (though considering Draco’s in the same scene I don’t think it’s supposed to be the Gryffindor tower allegorically).
Looking at the skyline more closely, positionally, it looks like it would be right where the replacement Training Grounds Tower is. I wonder if that’s why the TGT was removed – they originally intended for the AT to go there, and when they later settled on it being closer on the main model but forgot/didn’t want to send the budget to update the shot, they needed a quick replacement for the TGT they’d just destroyed. Granted the Dark tower was also missing, but perhaps they dind’t want it to get in the way of the shot when they first filmed it.
Interesting snapshot of what might’ve been a transitionary phase.
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I’m thinking the relocation in that shot was just for the sake of getting a better-looking shot. The actual angle from the correct location doesn’t look as interesting. They knew the tower’s correct placement early enough to build it into the set that way, after all.
I think the removal of the training grounds tower was just Stuart Craig removing real-world locations where he could. He wanted a more designy, less organic Hogwarts, which I can appreciate even if I don’t fully agree.
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How can you be sure that’s exactly what Craig wanted with the model? Did he ever say as much?
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Yeah, he’s given some interviews where he described the later films as providing some wish fulfillment for him. He didn’t like the untidy profile and the reliance on real-world locations in the early films. With the later films having bigger budgets for sets and VFX, he got to make some improvements (in his estimation at least). I believe he’s said that his favorite version is Deathly Hallows, and the ruined version from the end of the film even more.
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Wow, fantastic to see the AT, the progress is amazing to see!
I came across set photos of the AT, it was in the-making-of feature.
Set photo:
https://ibb.co/pv0mwvK
Daniel with interviewer on platform with a telescope in the third tower: https://ibb.co/BPWMCRQ
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Hey, I was wondering how you make all the bricks the same size. I have also set up a procedural material in blender but the size changes depending on the building. Thanks!
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You can use something like the Position attribute from the Geometry node as the vector for the brick texture!
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Hey, so a question for the expert that’s relevant to the Astronomy Tower, do you know where this shot is from?
https://static.wikia.nocookie.net/harrypotter/images/1/1c/Hogwarts_Castle_at_night_HBPF.jpg/revision/latest?cb=20091103085455
I’ve been trawling HBP and deleted scenes for it, but can’t find where it comes in.
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Imgur’d it because I always forget the wiki sucks for sharing links
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I want to say it came from a trailer? Must have been a deleted shot that just didn’t make the final cut.
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Oh btw Joe, could you do me a favour? Can you share what references you have for the astronomy lookout where Dumbledore dies please? Especially anything relating to the lower level underneath the main deck where Harry hides, though I also won’t say no to pretty much anything else of that part of the tower or of the big ‘ol telescope in the hole of the front of the tower and the metal stairs leading up to the lookout. Film 6 opting to be almost always as dark as possible is very striking, but it is not always super helpful for my purposes, and in my rpg DMing I want to set a scene there.
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My primary reference is the page of plans, sections, and elevations of the full-size set. It hangs on the wall at the Studio Tour. Here’s my composite of the best-resolution images I can find, with perspective corrected. https://hogwarts4dhome.files.wordpress.com/2021/09/astronomy-tower-set-drawings.jpg
Beyond that, I’m just using frames from the film (indeed very dark), plus a few photos of the white card model at the Studio Tour. Nic Henderson’s website also has a nice detailed view of the lookout tower that was added in DH, which is based on the same design as that part of the astronomy tower. https://nichenderson.wordpress.com/#jp-carousel-166
Good reference for the big telescope facing the front of the tower is elusive. The only shot I’ve seen of the inside is the shot where Harry runs into Snape on the spiral staircase before he goes off with Dumbledore to find the Horcrux. It doesn’t reveal much.
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Thanks! This has been very helpful – never had face-on shots of the blueprints before, much less one this hires.
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If it’s of any help, in the portfolio of this guy there are a few photos of the astronomy tower set: https://www.pierrebohanna.com/harry-potter-and-the-half-blood-pri
and this photo by Margaret Stranks shows the miniature quite nicely: Astronomy Tower https://imgur.com/gallery/3bbv1uz
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Good finds, I hadn’t seen those! Thank you!
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Hey, not exactly related to the astronomy tower but there’s a new video on the official wizarding world YouTube channel about the hogwarts model at the studio tour. Some really cool behind the scenes photos of the original model from the first film that I don’t believe have been seen before are in the video. I’ll link it if I can: https://m.youtube.com/watch?v=V_Lk1T2Pwsw
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Isn’t it insanely cool? I’ve got some corrections to make!
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You finally got your side profile of the reception room!!
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It’s so cool. It’s nice to see up close the Chamber of reception’s large front window too. It also appears some details are visible for that section of wall we never see on the Durham courtyard, above the cloisters in front of the chapter house. I desperately wish they had a photo of inside the quad tho. And what I would give to look through that binder!
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