# If we needed castles again, how would they be built? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [August 28, 2013, 5:04am UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372 "2013-08-28T05:04:31Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![drastic\_quench](https://avatars.discourse-cdn.com/v4/letter/d/e36b37/32.png) [@drastic\_quench](https://boards.straightdope.com/u/drastic_quench)\ **Post date:** [August 28, 2013, 5:04am UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/1 "2013-08-28T05:04:31Z")
Assuming for some reason people again needed castles to defend against old school medieval-type armies (no gunpowder, explosives, aircraft, tanks, ect for either side.) but we could build the castles using modern methods and materials – what would that castle look like? Pre-fab steel plates and scaffolding? Concrete and razor wire? ---
**Author:** ![aNewLeaf](https://avatars.discourse-cdn.com/v4/letter/a/ac91a4/32.png) [@aNewLeaf](https://boards.straightdope.com/u/aNewLeaf)\ **Post date:** [August 28, 2013, 6:40am UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/2 "2013-08-28T06:40:48Z")
We have bulldozers but not tanks? ---
**Author:** ![the\_diego](https://avatars.discourse-cdn.com/v4/letter/t/7bcc69/32.png) [@the\_diego](https://boards.straightdope.com/u/the_diego)\ **Post date:** [August 28, 2013, 9:25am UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/3 "2013-08-28T09:25:14Z")
All you need is a 12-foot high reinforced concrete perimeter wall. A lighter fence extension going up to 30 feet (65 feet if you want to copy the South Africans) will protect against hand-thrown projectiles. The entrances should be able to deny heavy wheeled vehicles and maybe some armored types. The structures inside should have reinforced roofs and fireproof construction. Oh yeah, you need two kinds of wells (a drilled jack pump and an open cistern) and adequate storage facilities. ---
**Author:** ![Sailboat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sailboat/32/461_2.png) [@Sailboat](https://boards.straightdope.com/u/Sailboat)\ **Post date:** [August 28, 2013, 12:23pm UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/4 "2013-08-28T12:23:44Z")
Well, this is somewhat outside the OP’s criteria, but might be of interest. I have seen various technical documents concerning securing modern buildings against attack, and one of the more interesting ideas is to surround the outside walls with a pile of loose, round rocks (not unlike piles of cannonballs one sees at historical sites, but all the way around the building). The concept, as I understand it, is that if the rocks are the right diameter, incoming RPGs and possibly shells will almost always tend to deflect away from a direct line as they pass between the rocks, thus failing to penetrate the building. Interesting idea I would look into if I were building modern fortifications. ---
**Author:** ![pancakes3](https://avatars.discourse-cdn.com/v4/letter/p/ba9def/32.png) [@pancakes3](https://boards.straightdope.com/u/pancakes3)\ **Post date:** [August 28, 2013, 1:18pm UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/5 "2013-08-28T13:18:33Z")
An oil derrick? An aircraft carrier. I’m pretty sure it’s trivial to build a large house that’s able to sustain Trebuchet hits. Even flaming trebuchet hits. Will the castle have modern defenses? Electric fences? Gun mounts? Cameras? Sharks with freakin’ laser beams attached to their freakin’ heads? It’ll essentially be a bond villain’s lair. ---
**Author:** ![msmith537](https://avatars.discourse-cdn.com/v4/letter/m/d9b06d/32.png) [@msmith537](https://boards.straightdope.com/u/msmith537)\ **Post date:** [August 28, 2013, 1:19pm UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/6 "2013-08-28T13:19:15Z")
> [@aNewLeaf](#): > > We have bulldozers but not tanks? It’s a hypothetical. Pretend your work site got magically transported back to the 1400s along with all the supplies, trucks and contractors. So the question is how we would build a castle using modern construction techniques to defend against a medieval army? I presume it would look pretty much like a medieval castle, but made from extra steel reinforced concrete instead of rocks. The walls might have a bit more slope to them to deflect away projectiles. If we couldn’t put it in the middle of a river or surround it with a moat, surrounding it with modern tank traps might be a good defense against siege towers and battering rams. ---
**Author:** ![lieu](https://avatars.discourse-cdn.com/v4/letter/l/c2a13f/32.png) [@lieu](https://boards.straightdope.com/u/lieu)\ **Post date:** [August 28, 2013, 1:25pm UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/7 "2013-08-28T13:25:07Z")
Don’t they use some kind of ceramic plates on the exterior of tanks now that absorb and/or deflect incoming armaments, preventing them from expending their energy against the actual tank exterior? I think I’d include that kind of technology to the castle exterior wherever appropriate. Also a Phalynx CIWS because, well, they’re just really cool. ---
**Author:** ![Ludovic](https://avatars.discourse-cdn.com/v4/letter/l/7ab992/32.png) [@Ludovic](https://boards.straightdope.com/u/Ludovic)\ **Post date:** [August 28, 2013, 1:32pm UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/8 "2013-08-28T13:32:21Z")
The central citadel could be a [Flak Tower](http://en.wikipedia.org/wiki/Flak_tower) which were fairly resistant to even explosive shot, so would be well nigh impenetrable to thrown rocks. The wall towers could be shorter versions of the flak towers but perhaps rounded off for line of sight purposes. ---
**Author:** ![msmith537](https://avatars.discourse-cdn.com/v4/letter/m/d9b06d/32.png) [@msmith537](https://boards.straightdope.com/u/msmith537)\ **Post date:** [August 28, 2013, 4:05pm UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/9 "2013-08-28T16:05:50Z")
> [@lieu](#): > > Don’t they use some kind of ceramic plates on the exterior of tanks now that absorb and/or deflect incoming armaments, preventing them from expending their energy against the actual tank exterior? I think I’d include that kind of technology to the castle exterior wherever appropriate. I think you are thinking of [reactive armor](http://en.wikipedia.org/wiki/Reactive_armour). I don’t think they use ceramics (although ceramic plates are used for armor). Usually it’s explosive or non-explosive plates designed to absorb or deflect shaped charges. > [@Ludovic](#): > > The central citadel could be a Flak Tower which were fairly resistant to even explosive shot, so would be well nigh impenetrable to thrown rocks. The wall towers could be shorter versions of the flak towers but perhaps rounded off for line of sight purposes. Sounds like those would be pretty tough for a modern army to take down. ---
**Author:** ![drastic\_quench](https://avatars.discourse-cdn.com/v4/letter/d/e36b37/32.png) [@drastic\_quench](https://boards.straightdope.com/u/drastic_quench)\ **Post date:** [August 28, 2013, 5:06pm UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/10 "2013-08-28T17:06:50Z")
> [@msmith537](#): > > It’s a hypothetical. Pretend your work site got magically transported back to the 1400s along with all the supplies, trucks and contractors. > > So the question is how we would build a castle using modern construction techniques to defend against a medieval army? Exactly. ---
**Author:** ![Johnny\_Bravo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_bravo/32/493_2.png) [@Johnny\_Bravo](https://boards.straightdope.com/u/Johnny_Bravo)\ **Post date:** [August 28, 2013, 5:20pm UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/11 "2013-08-28T17:20:20Z")
> [@msmith537](#): > > I think you are thinking of [reactive armor](http://en.wikipedia.org/wiki/Reactive_armour). I don’t think they use ceramics (although ceramic plates are used for armor). Usually it’s explosive or non-explosive plates designed to absorb or deflect shaped charges. lieu might be thinking of ablative heat shields, which are sometimes made from ceramic composites and have been used on space craft to deal with the heat of re-entry. ---
**Author:** ![robert\_columbia](https://avatars.discourse-cdn.com/v4/letter/r/e79b87/32.png) [@robert\_columbia](https://boards.straightdope.com/u/robert_columbia)\ **Post date:** [August 28, 2013, 6:22pm UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/12 "2013-08-28T18:22:22Z")
One thing I would think would be helpful is building _tall_ towers. Being higher up gave a rather large advantage in those days. With modern technology (say, steel skyscraper construction with girders), we could build turrets that go up ten times higher than would have been feasible in those days. I wouldn’t be so quick to rule out gunpowder. They did have firearms in the Middle Ages, you know? Sure, they weren’t up to the level of howitzers and AK-47’s, but you could give a guy a gun and tell him to point it over there and shoot and once in while he did hit. ---
**Author:** ![drastic\_quench](https://avatars.discourse-cdn.com/v4/letter/d/e36b37/32.png) [@drastic\_quench](https://boards.straightdope.com/u/drastic_quench)\ **Post date:** [August 28, 2013, 7:38pm UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/13 "2013-08-28T19:38:46Z")
I know about gunpowder, but I want to exclude it, because we’ve already got the answer to that question in the form of napoleonic and Civil War era fortifications. ---
**Author:** ![bump](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@bump](https://boards.straightdope.com/u/bump)\ **Post date:** [August 28, 2013, 8:51pm UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/14 "2013-08-28T20:51:41Z")
I’d think the biggest threat would be siege engines, mining and infantry. Infantry are pretty easy; big trench and high wall on the far side. Mining would be easy with 21st century building technology; just pour massive reinforced concrete foundations that they can’t dig under. Siege engines would be the next one; I’d think that the high wall mentioned would need to be a kind of inward sloping thick concrete wall with barbed wire at intervals, and within that wall, another one with a sloping top section, and a vertical section below, with arrow slits to be able to shoot down the length of the sloping outer wall. I might even consider putting my keep on 20 foot high columns with some sort of nifty elevator system that could be retracted, so that even if they did get inside the inner curtain wall somehow, they’d be stymied at getting into the keep. I’d think that water would be a big issue that we could do the Medieval engineers one better on- maybe figure out how to either come up with a foolproof passive purification materials system that would keep stored water fresh, or maybe a really deep well and clever, really durable pumping system. ---
**Author:** ![Bosda\_Di\_Chi\_of\_Tricor](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bosda_di_chi_of_tricor/32/16845_2.png) [@Bosda\_Di\_Chi\_of\_Tricor](https://boards.straightdope.com/u/Bosda_Di_Chi_of_Tricor)\ **Post date:** [August 28, 2013, 9:17pm UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/15 "2013-08-28T21:17:59Z")
> [@bump](#): > > I’d think the biggest threat would be siege engines, mining and infantry. > > Infantry are pretty easy; big trench and high wall on the far side. > > Mining would be easy with 21st century building technology; just pour massive reinforced concrete foundations that they can’t dig under. > > Siege engines would be the next one; I’d think that the high wall mentioned would need to be a kind of inward sloping thick concrete wall with barbed wire at intervals, and within that wall, another one with a sloping top section, and a vertical section below, with arrow slits to be able to shoot down the length of the sloping outer wall. > > I might even consider putting my keep on 20 foot high columns with some sort of nifty elevator system that could be retracted, so that even if they did get inside the inner curtain wall somehow, they’d be stymied at getting into the keep. > > I’d think that water would be a big issue that we could do the Medieval engineers one better on- maybe figure out how to either come up with a foolproof passive purification materials system that would keep stored water fresh, or maybe a really deep well and clever, really durable pumping system. If the attackers dig tunnels, & set large fires beneath your foundations, the uneven heating & colling could cause you some nasty problems. In all cases, wall should be **rounded** –no sharp corners for siege machines to exploit. Re–walls & infantry. Imitate the wall system of Constantinople. > **[Walls of Constantinople | Theodosian Walls](https://en.wikipedia.org/wiki/Walls_of_Constantinople#Theodosian_Walls)** > > The double Theodosian Walls (Greek: τεῖχος Θεοδοσιακόν, teichos Theodosiakon), located about 2 km (1.2 miles) to the west of the old Constantinian Wall, were erected during the reign of Emperor Theodosius II (r. 402–450), after whom they were named. The work was carried out in two phases, with the first phase erected during Theodosius' minority under the direction of Anthemius, the praetorian prefect of the East, and was finished in 413 according to a law in the Codex Theodosianus. An inscription... On a smaller scale, of course. ---
**Author:** ![jasg](https://avatars.discourse-cdn.com/v4/letter/j/f0a364/32.png) [@jasg](https://boards.straightdope.com/u/jasg)\ **Post date:** [August 29, 2013, 2:00am UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/16 "2013-08-29T02:00:16Z")
Outside the parameters in the OP, but interesting - a new [castle](http://www.guedelon.fr/en/) is being built in France. ---
**Author:** ![Johnny\_Bravo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_bravo/32/493_2.png) [@Johnny\_Bravo](https://boards.straightdope.com/u/Johnny_Bravo)\ **Post date:** [August 29, 2013, 2:09am UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/17 "2013-08-29T02:09:09Z")
> [@Bosda\_Di\_Chi\_of\_Tricor](#): > > If the attackers dig tunnels, & set large fires beneath your foundations, the uneven heating & colling could cause you some nasty problems. I imagine that enough basement sub-levels with lots of steel and concrete reinforcement would stymie any medieval sapping attempts. ---
**Author:** ![shijinn](https://avatars.discourse-cdn.com/v4/letter/s/cc9497/32.png) [@shijinn](https://boards.straightdope.com/u/shijinn)\ **Post date:** [August 29, 2013, 2:48am UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/18 "2013-08-29T02:48:07Z")
1. build a huge but shallow and sandy artificial lake around the castle to deter heavy equipment. 2. release the piranhas. 3. as a last resort, release the petroleum reservoirs into the swamp and ignite it. 4. drain the lake and dine on roast pig. ---
**Author:** ![lisiate](https://avatars.discourse-cdn.com/v4/letter/l/f05b48/32.png) [@lisiate](https://boards.straightdope.com/u/lisiate)\ **Post date:** [August 29, 2013, 3:39am UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/19 "2013-08-29T03:39:42Z")
> [@jasg](#): > > Outside the parameters in the OP, but interesting - a new [castle](http://www.guedelon.fr/en/) is being built in France. You sell it short - that’s more than interesting - it [looks awesome](http://www.kuriositas.com/2010/07/guedelon-castle-new-medieval-chateau.html)! ---
**Author:** ![the\_diego](https://avatars.discourse-cdn.com/v4/letter/t/7bcc69/32.png) [@the\_diego](https://boards.straightdope.com/u/the_diego)\ **Post date:** [August 29, 2013, 3:55am UTC](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372/20 "2013-08-29T03:55:15Z")
The one most crucial improvement using modern tech: a working sewerage system and running water. Don’t resurrect the cesspool cleaner, OK? [Next page](https://boards.straightdope.com/t/if-we-needed-castles-again-how-would-they-be-built/667372.md?page=2)