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In S07E01 - Dragonstone, the gates of Dragonstone open inwards.

Why? Isn't it easier to ram down when it can be pushed open? The hinges are high enough to be inaccessible, and could easily be reinforced/hardened during wartime.

The door opens

amflare
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Jedi
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    Oh good question! Outward-opening gates would probably be harder to break down. – Obsidia Jul 17 '17 at 20:17
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    I've had to down-vote because of a lack of research. How would a bartering ram work if you had outward opening gates (here's a clue, it wouldn't) also look at your door, if it was outward opening the hinges would be on the outside. Pop that off, and you might as well start singing Timber by Pitbull – Edlothiad Jul 17 '17 at 20:45
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    This is not a good question as it show a complete lack of research effort. As the given answer shows it is firmly based in real life. – Skooba Jul 17 '17 at 20:45
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    @Edlothiad, I addressed the argument concerning hinges in my question; this was the most common reason from medieval history. also indicating "research", Skooba. :-) However, this is not a good enough reason, as I mention above. – Jedi Jul 17 '17 at 20:50
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    Even if the hinges are high, the attackers only need a single person to reach them. It might be easy to bring a covered ladder and send people up with hammers, chisels and archer cover. Even if you lose some of them, only one needs to succeed. This is different from scaling walls, where you need to get as many people over as possible. – Samthere Jul 18 '17 at 08:42
  • Note that the gate is way too big - and still easily opened by two guys pushing on the doors. That's not something that would be resistant to battering anyway. There's plenty of other things that suggest it's not a particularly good castle design. – Luaan Jul 18 '17 at 08:42
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    @Luaan: "That's not something that would be resistant to battering anyway." Doors can have weights attached to make it easier to move them (easier than when you only consider the weight of the door itself). Furthermore, doors do not stay closed because of their weight; they would still be barricaded. – Flater Jul 18 '17 at 14:43
  • @Flater Weights do not help against inertia - they make it worse (you need to also get the weights moving). I wasn't considering that doors stay closed because of their weight - I was considering that given how flimsy the doors appear, they would be broken (rather than "rammed through"). Bracing doesn't help you if the door splinters into a thousand pieces. – Luaan Jul 18 '17 at 15:08
  • @Luaan: Weights by themselves, yes. Weights on a pulley system, no. If the weights are measured to be just below the needed force to move the door, then these two people only need to apply the additional force, which (depending on the accuracy of the used weights) can be very minimal. (If you're wondering: for closing the door, which would become harder due to the weights, they can be detached, pulled up, and reattached.) You're correct about breaking flimsy doors, but I don't think they are flimsy doors. – Flater Jul 18 '17 at 15:15
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    I've voted to close this question as off-topic because in essence it has no tie to science fiction or fantasy beyond the show it appears in. We could ask countless question about "Why is XYZ this way in GoT?" that all answers boil down to "that what was done in the real world". – Skooba Jul 18 '17 at 17:33
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    @Skooba You're saying this question is off-topic because a part of a fictional universe was inspired by real-world things? I don't think it works that way. – Gallifreyan Jul 18 '17 at 18:07
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    @Gallifreyan IT would be like asking "Why do they wear armor in GoT?", "Why do ships have sails in GoT?", by adding "in GoT" does not automatically make a question on-topic. – Skooba Jul 18 '17 at 18:08
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    @Skooba Why is that? If it's within the context of the work, I don't see why it should ever be off-topic. doesn't it add to one's understanding of the work to know a little historical background? I'm not saying this question is great, and it may seem trivial, but it's definitely on-topic. I'm sure there are lots of questions on this site that benefit more from real-world explanations than from in-universe ones. – Gallifreyan Jul 18 '17 at 18:12
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    @Gallifreyan Much like its linked question that was closed, I disagree. "Why is the sky blue in GoT?", "Why are there lemon cakes in GoT?".... – Skooba Jul 18 '17 at 18:17
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    @Skooba I agree. This might as well be explicitly asking for real-world science, rather than implicitly, like it is. – DCOPTimDowd Jul 18 '17 at 18:19
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    @Skooba You can also vote to close this then. The problem is, in order to close questions such as this as off-topic, we'd need to know beforehand that it's more about real world than about the fictional world and the author's imagination. how can we judge that before seeing the answer? – Gallifreyan Jul 18 '17 at 18:21
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    @Jedi No, our policy states "On the other hand, most fictional works, even pure fantasy ones, operate with an implicit assumption that the laws of physics in the movie work just like the laws of physics in the real world, unless/until the work shows us differently. So many legitimate questions about the fictional universe will end up being answered using real-world science, because it's the same as the fictional science" – Skooba Jul 18 '17 at 18:28
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    @Skooba I'm not sure you actually read the question or answer (both of which I wrote) because you're getting it backwards: Any question that is asking for an answer within the context of a fictional universe, even if that question requires real-world science information, is on-topic. This question is clearly being asked within the context of the Game of Thrones universe. – KutuluMike Jul 18 '17 at 19:14
  • Also note that asking questions specifically to make a point that you disagree with site policy is a good way to get suspended. – KutuluMike Jul 18 '17 at 19:16
  • @Jedi yep. it happens sometimes. poorly-received questions often get incorrectly closed as people struggle to figure out what to do with them. – KutuluMike Jul 18 '17 at 20:49
  • So an army with massive siege engines to batter down inward-opening gates, and ladders and similar wall-scaling equipment (to get over the entire walls) would be thwarted by hinges that would require a step-ladder to access? I'm not sure that bit actually "dealt with" the issue adequately. – PoloHoleSet Jul 18 '17 at 20:56
  • Your other question has been reopened :-) (For the record, I upvoted both. I'm not sure why people have been criticising them so much - you've clearly put some thought into the practicalities of attacking a castle, and your questions make sense.) – Rand al'Thor Jul 18 '17 at 23:15
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    @Skooba: Just as a side note: If you insist on this post being closed, that one: https://scifi.stackexchange.com/q/127843/44517 Has to be closed for the very very very same reason ;) But in my opinion both are on topic. But this one more then yours. – Zaibis Jul 20 '17 at 05:30
  • @Zaibis How is character identification in any way related to this? Are you asking for the gate in your question to be identified? – Skooba Jul 20 '17 at 12:00
  • @Skooba: Well, than it had be to closed as it is asking 2 diferent questions. I was focused on the "Why does he wear white?" part of your question which is answered by your accepted answer with "... it might be tied to his position as Deputy Director of Naval Intelligence much as with the United State "Full Whites" naval uniform..." What is in a break down nothing but asking "Why a uniform has a colour in starwars?" Whats exactly what you made fun over this post. – Zaibis Jul 20 '17 at 12:16
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    @Zaibis If I had asked "Why do they wear uniforms in Star Wars?" then maybe I could see your point. – Skooba Jul 20 '17 at 12:35
  • Well you asked for white uniforms instead. But if you can't see my point, nvm. – Zaibis Jul 20 '17 at 12:37
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    @Skooba Exactly that. Even if this was asking why a certain castle chose a particular type of gate based on some different assumption, making it a little more in-universe, it'd still be asking for a more real-world explanation. Given the current accepted answer, there is nothing tied specifically to GoT that is necessary to explain why the gates are they way they are. So any little bit of research done beforehand could have turned up the same results. – DCOPTimDowd Jul 20 '17 at 16:35
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    In fact, here is an old reddit asking almost the exact same question, this quora question from earlier this year, and then here's a history on castles in Ireland which mentions why doors opened inwards. All this from the first page of my Google search of "castle gate open inward". – DCOPTimDowd Jul 20 '17 at 16:57
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    https://movies.stackexchange.com/a/76428/9164 – Pete Kirkham Jul 21 '17 at 09:44
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    Because the doors were made before OSHA rules saying any emergency exit doors must open outward? – RichS Jul 24 '17 at 03:43

4 Answers4

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This is how the castle doors/gates work in real life for various reasons.

  • To open outwards, the hinges would need to be on the outside. Not an ideal design.
  • It is easier to push gates closed against an enemy than to pull them closed.
  • Doors that open inwards are always under the control of the castle and protected by the stonework.
  • You can barricade the door from the inside with rubble to prevent access.
  • In case of attack, the people closing the door are protected.
  • Gates are usually barred, rather than locked, which needs to be inside the door and is easier if the gate opens towards the bar.

Here are some real castle gates for reference

castle gate 1 castle gate 2 castle gate 3 castle gate 4

amflare
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    Comments are not for extended discussion; this conversation has been moved to chat. – Null Jul 18 '17 at 18:14
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    Additionally: it's a lot harder to block an inwardly-opening door from the outside. It would be quite the prank to hammer a spike in front of a door and lock the inhabitants inside. Well, the inhabitants might not find it funny... – ArmanX Jul 20 '17 at 18:16
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This is an interesting physics problem. Counter intuitively, it looks like opening inward is actually stronger!

From a strength perspective, it doesn't matter whether the doors open inward or outward. What matters is whether an attacker's actions cause tension or compression. If you have the typical doors you see in castles, a battering ram hit causes tension - the wooden beams pull against each other to resist the ram. If you bow the doors out a bit, you can see that they cause compression instead. Trying to ram the doors causes the doors to try to close more, compressing all of the timbers.

Different materials handle tension and compression in different ways. Concrete, for instance, is very good at compression loads but falls apart under tension loads. Accordingly, you'll always see concrete structures in compression. Look at a bridge, and you'll always see an arch to it, ensuring the whole bridge is in compression.

Wood, on the other hand, is much better at tension loads. Compression loading focuses all of the forces on one part of the door, while tension loading lets wood do what it is best at. If you rammed a door in compression, the wood would rapidly splinter, rather than bending to soak up the energy and momentum. (There's more to it, dealing with cross grain and along-the-grain forces, but that's another physics lesson)

So you definitely want a door structured so that battering rams cause tension. If you run the geometry, you see that it's really hard to have a door open outwards and exhibit tension under attack.

Cort Ammon
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    Does this really matter, given the door isn't bowed but rather plane when closed? There's always tension when it bends inwards at being hit from outside. Regardless whether it's held in place by hinges and locks, or pressed against the frame. – Bergi Jul 18 '17 at 17:48
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    @Bergi If the door is a flat pane, then that would work as well, but then you'd have to be really careful with your construction to make sure the hinges are ready to be bent backwards under the force of a strike. The construction of a door that is under tension when attacked and opens inward is a much easier construction problem than one that opens outward. – Cort Ammon Jul 18 '17 at 18:15
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    So actually "run the geometry", along with some diagrams. At the moment, this answer as it stands is far inferior to those below it, regardless of the checkmark. You wouldn't "need to make sure hinges [were] ready to be bent backwards": external hinges would simply be destroyed. Similarly, closed concrete doors would chip just the same way wood splinters, without any regard to which way they normally opened. – lly Jul 20 '17 at 01:34
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    tl;dr: At the moment, this answer sounds smarter than it actually is. It's already less on topic than those below it but could still be mostly salvaged, assuming you actually do understand the physics involved, by demonstrating that knowledge in some test cases and comparisons. Start with the fact that none of the doors are bowed and that battering it bows them all in, not out. – lly Jul 20 '17 at 01:36
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    Wood is better than concrete at tension, but tension isn't what wood "does best", it is still considerably stronger in compression than tension. – whatsisname Jul 20 '17 at 13:31
  • @whatsisname Interesting. The sources I looked at said wood was 2-3 times stronger in the tension direction. I wonder if one of our sources is looking at a static scientific number, while the other is looking at the more dynamic nonlinear strengths of wood. I do so love it when something's complicated enough to find conflicting sources! Especially when it's something we take for granted like wood! – Cort Ammon Jul 20 '17 at 15:02
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    This doesn't make much sense. Do you have any evidence that this is the analysis used by either actual medieval people or the inhabitants of the Game of Thrones world? Also, the weakest point of a gate is probably where it attaches to the walls, not the door itself. The other, common sense answer that doesn't attempt to use science unavailable to medieval people is much more reasonable. – jpmc26 Jul 20 '17 at 22:57
  • "Counter intuitively, it looks like opening inward is actually stronger!" Do you mean outward? – Code-Guru Jul 22 '17 at 01:43
  • don't know about the others but i feel truly enlightened :D – conquistador Jul 24 '17 at 05:49
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For small doors which are thick relative to their size such as the hatch on an army tank it makes sense to open outwards. Castle doors are very large and relatively thin for their size. Since a battering ram places it's force in the middle of the door it will snap the timbers of both inward and outward opening doors equally well. Most of the strength of these doors comes from the portcullis behind it and/or cross braces and other support timbers put in place during a siege not from which way they swing.

So you might as well have them open inward to protect the edges of the door (which are considered the weakest part) and for the other reasons that amflare mentioned.

John Ray
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  • A tank hatch doesn't have the same design goals - firstly, opening inwards means the occupant has to have space to move out of the way, and space inside the hull is limited, secondly it is resisting blast force not attempts to open the hinges. – Pete Kirkham Jul 21 '17 at 08:57
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Others have made good points, but I think the simplest explanation is probably this: large gates like that are usually barred, not (just) locked. You want to be able to bar and unbar the door from the inside, and for that to work, it has to open inward.

SirTechSpec
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    Technically you can bar a gate from the side it opens away from. You'll just be pulling against the bar rather than pushing against it. – amflare Jul 19 '17 at 20:53
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    Hmm, I suppose you could... it would require having hooks on the side of the door itself that faces the bar, though, strong enough to keep it closed. An awkward engineering problem with a lot of points of failure compared with just pressing relatively-evenly against the whole length of the bar (presumably secured at the ends.) – SirTechSpec Jul 19 '17 at 20:56
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    @amflare. Usually you would not take just one bar to reinforce the gate. That's the primary reason for a portcullis, to reinforce the gate against attacks. And it is technically very difficult to use a portcullis in any sensible way if the gate opens to the outside. It is however a lot easier to reinforce the gate with a portcullis when it opens to the inside. – Adwaenyth Jul 20 '17 at 07:39