Why did we stop building castles?

Castles are may be the most important thing in medieval age along with sword and armor. I love all of them. Castles are mainly used by nobility or royalty. These fortified buildings can be found all across the globe. I like not only real-life castles but also fantasy castles too. Every fantasy novel , tv show or a movie has at least one big castle. My favorite is - if its even considered a castle - minas tirith. I think it can be called a type of a castle. It has walls, it is fortified, has siege defensive wepons, has multilevel structure to defend the inner circles etc.

Castles was the main big thing for medieval lords to defend their territory. If you have strong castle you can withstand sieges for a long time. They were really hard to build and maintain but extremely efficient to defend the city and the people inside it. Not the mention they look badass. But why did we stop building them?

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War Technology

The first impact to the castles comes from the perspective of the war technology. In medieval times, the main power was the menpower. More soldiers and warrior you have the more power you posses. In time people use their skills to develop machines to overpower men and eventually man made strong structures. But this does not mean the end of the castles. The technology of war machines such as trebuchet , mangonel , catapult, cannons , only change the shapes of the castles. They build stronger walls, and anti siege machines on the walls. But the technology keep developing and its not only in the military area. Logistic is the most important thing when its comes to sieging a castle. The main purpose is not the destroy the castle and kill everyone inside. The goal is to have all the food available from outside of the castle to you while you cut the supply to the castle to starve them. Usually , castles have monts and sometimes years of food. Siege is a game of food, not sword and armor. This takes us to the second point.

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Logistics

With war technology developing, transportation and logistic is also developed on the side. In time people can move quickly in long distances and can carry lots of food with them. This rendering castles more useless. Imagine an army that has lots of food available to them while the castle defenders only have limited amout to withstand the siege. Locking yourself behind a wall with limited food and water supply isnt a smart thing when your enemy has almost unlimited supply due to more advanced logistic technology.

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Super Expensive

Even today with modern technology and modern machinery, building a castle is a huge project. Its hard , expensive and takes really long time. When you dont really have an advantage of having a castle anymore due to previous reasons , its not logical to build something not effective and efficient. With the discovery of gun powder and other technological development , the war strategy goes towards defending territories, strategic places and farm lands etc. Money goes to military, guns and training, rather than building a huge stone walls which takes years and years to build and not be effective.

If you want to see a modern time castle build and how hard it is you can watch the documentary about a castle build in france. The Guédelon castle.

The image above shows the layout of the castle. It is not done yet but most of it is already build using medieval time technology. They are living in a village like a time machine. Everything including, tools, techniques, materials and clothing is medieval. The construction started in 1997 and still continue.

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You can see the photos of the castle through different years in wikipedia page