Would medieval fortifications be effective in a zombie apocalyptic world?

Question

Living in Budapest I see almost everyday the Budapest Castle. Being into zombies I often wonder how useful could be a castle of this kind in a world where zombies taken over.

Most, if not all, the zombies movies and tv shows are set in America, where solid buildings aren't common as in europe, and medieval castles aren't present. So there aren't chances to see survivors try to adapt this kind of buildings to survive against zombies.

The castels I'd like to take in consideration are the ones in good status, without flaws in the walls and generically easy enough to be further fortified to defense their entries.

How plausible would be for a group of survivors , in a post apocalyptic world full of zombies (like the ones of the most common movies: slow and unorganized) to fortify a castle and live there for an undefined period of time?

I'd like to see all the possible factors covered: other groups of hostile survivors, demography (and related number of potential zombies) of the areas near the most famous castles and so on.

The timeframe should be modern days (2017).

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This question is different from Castle Moat Full of Zombies because I'm not asking how to keep the moat empty, I'm asking about the feasibility of living inside a medieval castle during a zombie apocalypse, with all the concerned problems considered.

Answer 1

Short answer: absolutely.

Long answer:

Given that castles are, by their nature, fortifications, you would be hard pressed to find a more defensible building in the world (other than in an operational military base, at least). Using a castle in a zombie apocalypse scenario would have several pros and cons, as expressed below.

Pros:

A castle is made entirely of strong walls, which are designed to deter entry and keep enemies out. Zombies, being of minimum intelligence, will be unable to penetrate strong walls so long as they are in good condition.

Almost every medieval style castle was built with active defense in mind. This means that man castles have ports to fire arrow from. Also, there tend to be locations to drop hot oil or other substances onto intruders. These ports and holes can be modified or used outright for rifle-wielding people, and if they are close enough to the ground, pole-arms and bayonets are also an option.

Castles tend to have high points, which are made for increased vantage for intelligence gathering. For the most part, any intruder is visible for miles, and slow moving zombies could be watched for days as they move either towards away from your fortification.

Castles tend to have multiple layers of defenses. This is known as defense-in-depth, and means that even if zombies make it past one layer, you have another ring of walls to fall back behind and continue defending with as of yet unbroken defenses.

Cons:

Castles are large. Large buildings require either highly mobile or a lot of defenders to properly defend from active threats. If humans got involved, you'd be hard pressed to keep the whole thing defended.

Castles tend to be somewhat complex. If there are weak points anywhere that a zombie could get through, several of them could be in your castle before you even know it.

Many castles are not well ventilated or very modern in terms of human safety. You run the risk of such things are mold and other growth making the humans that live there sick and less effective as defenders.

Most castles are old, and lack certain design features like power distribution and plumbing. Most of those services won't really work in the apocalypse scenario anyway, but having them just in case sure would be nice.

Conclusion:

I'd say, assuming you had no better options, a castle would be a wonderful place to set up for a long defense against zombies. Perhaps the closest modern analogue would be jails, although jails are mostly designed to keep people in, not always out.

There is a series of zombies that uses a jail as its location for several episodes (The Walking Dead, seasons 3 and 4) and this series manages to outline some great pros and cons to the hard-building approach to survival.

Answer 2

Two things about castles that make them less effective against zombies than people:

1. All that stuff that protects against siege engines and sappers is wasted on zombies. They don't do intelligent things like pick up trees to slam into the wall or gates. They don't try to dig under the walls. A castle is not nearly as much better than a brick house against zombies than as if it were defending from people. That said, any building where the doors can be locked is an advantage against zombies.

2. A major part of how zombies work is infiltration. Someone gets bit and doesn't tell anyone. Then they die inside the castle and turn into a zombie. Then they bite a second person. Now there's two zombies. Repeat until everyone's dead. Walls don't protect from a danger that is already inside. Under Walking Dead rules, the person doesn't even need to get bit. It's enough to die inside.

Beyond that, what happens when zombies surround the castle? Sure, they can't get in. But if you can't get out, you die of starvation.

A jail is a safer place in a zombie apocalypse. Lock yourself in the cell at night. Keep a supply of food in the cell. If something goes wrong, you're in a locked room. Stab the zombie(s) through the bars. Use the security system to track whether a zombie ended up inside. Keep the section doors locked to limit the scope of any problem.

If you do find yourself defending a castle in the zombie apocalypse (perhaps others took all the jails in the housing raffle), try to make the castle more like a prison. Make it possible to lock each room's door. Add chokepoints inside the castle halls that are easy for people to open but difficult for zombies. Add security cameras so as to monitor the halls (a castle that was a museum would work). Add a garden inside the walls. Keep the doors closed at all times. Open only when you have good visibility.

Try for a castle with a gate with a double portcullis. Open one to let some zombies into the vestibule. Drop it behind them (perhaps on some of them). Then stab them with spears through the other portcullis. Eventually open it and clean out the vestibule. Repeat until there are no more zombies blocking the gate.

Castles have solid walls. They are protected from attack from the outside. These walls are better than most fences against zombies, as they were built with the possibility that there might be attacks by pressing against them from outside. That may make them slightly more effective than more modern fortifications, which assume weapons capable of piercing them. Zombies don't have that ability. Their power is in massing together and brainlessly pushing.

Answer 3

As has been pointed out, castles are great for defense but rely on stored food and water in times of siege. The better castles have wells. Also, castles are usually situated on high ground and have good line of site.

Some strategies to make this work:

Use hand weapons to clear the zombies from the walls and gate. After entering the castle, close the outer gate and every internal door you find. Slowly do a section search (securing doors behind you) of the castle to clear it.

Once clear, start clearing the outside with hand weapons. If you can reach their heads from the top of the walls, great. Otherwise, use the human bait method to lure groups of zombies into kill zones (the double portcullis works well for this). Roam the local area in packs and lure more and more zombies into the trap.

Now, you can start growing food. If watch is kept on the walls/towers of the castle, you can spot zombies before they get to the farmers (just don't farm past the castle's field of view).

If, in your world, zombies only eat humans and leave animals alone, you can even raise sheep or cattle.

Everyone sleeps in locked rooms. At night, zombies can't get in and someone who does in their sleep doesn't get to go on a killing spree. The injured should be isolated.

Building forts on nearby high spots will let you expand. They can watch farmland further out and provide bolt holes for the farmers so they don't have to make it all the way to the castle.

A solvable problem will be getting rid of the smelly corpses but carrying them downwind once the area is cleared will work.

As has been mentioned, your biggest threat after starvation are any other humans who think that living in a castle is a good idea and who either don't want to share or think that they should be the ones running things.

Of course, that's the thing that castles were actually designed for.

Answer 4

Well...

picture taken from "World War Z"

Your group of survivors is doomed to die.

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Okay, only slow and unorganized zombies:

Sure, they can survive. These castles were able to defend against armies of organized soldiers, why would they fall to some zombies?

But while they can't overthrow you, they can besiege you. And

the most common [zombie] movies

tend to give them decades of lifetime after their transformation. So food and water will be your biggest problems. Starvation will kill your survivors. Especially because these castles hadn't todays methods of food preservation.

But stay relaxed, if your guys are lucky enough to find a full food storage all for themself, I'll give them about two years or so. As it is your world, you can let your zombies rot away in that time.