The appearance of a canonball altered the architectural design. Arrows (and stones thrown by a trebuchet) are readily stopped by a wall (square or round), but canonballs are not, thus they began to build circular towers to make canonballs slip on the wall rather than smash it. These towers were called donjons.
Donjons were first used in Europe around 1180. They were initially built as watchtowers for guards, but over time they became more useful as barracks, prisons, and even courts. The Knights Templar used them as military headquarters during wars. Donjons were also used as royal palaces, especially during the early years when many countries were still in the process of being established.
There are three types of donjons: defensive, administrative, and religious. Defensive donjons were used to protect castles and towns from attacks by enemies with weapons such as arrows and bombs. They could be small, like those at Conneford and Pendower, or large, such as those found at Caerphilly Castle or Saint-Guilhem-le-Désert in France. Administrative donjons were used by lords to administer their lands. They were usually located near towns or cities where they would have facilities such as jails, markets, and schools. Religious donjons were used by priests and monks as places of worship.
Round towers were more difficult for attackers to bring down. They had no corners, unlike square towers, which toppled if holes were excavated beneath the foundations. These provided a safer way of launching arrows at the castle's assailants. Defenders also had an advantage because they could hide in these holes and shoot their enemies from above.
Towers were also better suited for defense than walls would have been. A tower's defenders could fire down on attacking soldiers or use other means to harass them. This is why castles built after 1066 are mostly towers instead of walls.
The main reason people switched to towers was because it was easier to build one than a wall. There were also advantages to building a tower rather than a wall. For example, a tower could be higher or wider than necessary for defensive purposes while still providing cover for the actual defenses. This reduced the amount of land needed for the project and also saved money.
People also built towers when they wanted to send a clear message to others. If you built a big, expensive tower, then you were saying that you were important and should be treated as such. Some towers were even used as prisons until very recently.
Finally, towers were popular with royalty and wealthy individuals because they could afford to build them.
Round towers [also known as drum towers] withstand siege technology better. The round front of a square tower, like a load-bearing arch, is more robust than the straight side of a square tower. It provided the archers with a 360-degree view of the countryside surrounding the castle, making it simpler to shoot arrows because there were no corners. Soldiers could also climb up inside the tower during sieges for protection or as a place to make war preparations.
Towers made of stone were initially built in Europe around 600 AD. However, it was not until about 1100 AD that steel weapons began to appear in military campaigns. With no way to protect themselves from attack, the towers became symbols of strength and power. In fact, a knight would often wear armor designed specifically for climbing inside a tower if he had enough time to spare; otherwise, he might just go naked!
The first recorded use of the term "round" to describe a tower comes from 1166. The word probably came from the French "roue," which means "wheel." This is likely why some sources claim that round towers are wheeled towers. However, others say that they're called round because they resemble large wheels, which is how they got their name in English (though "drum" may be more accurate since they used to be made of wood).
There are three main types of round towers: machicolated, bartizan, and balustraded.
A battlement was a wall built on the roof of a fortress. They featured taller walls, known as merlons, with smaller spaces between them, known as crenels. Defenders would use crossbows to fire arrows through the crenels before hiding behind the upper merlons. Men-at-arms used swords and spears.
The best defense is a good offense. That's why knights were famous for their charge attacks, where they would run at the enemy with their sword drawn. These attacks could happen at any time, even if the enemy had returned to their camp after a battle had been fought or were just walking around their own territory.
If a knight was being attacked by several enemies at once, they would try to push them away from themselves. Then they would fight only one at a time! Although it was dangerous because you might get hurt while fighting others at the same time, it was better than being killed outright.
That's why castles had large areas surrounded by high walls. This made it hard for attackers to reach the gates without being seen or heard by someone inside the castle. Once they did, they would have to fight all the way up to the top floor where the defenders lived.
There were two ways to attack a castle: siege warfare and combat. In siege warfare, teams of soldiers would work together to destroy parts of the castle's infrastructure, such as roads or bridges.
Every aspect of its building was meant to ensure that the castle was as sturdy as possible and could withstand sieges that may last months. A significant innovation in castle building technology emerged in the late medieval period (about the 1300s): the concentric castle. Previously, all medieval castles were linear structures with an outer wall and an inner ward but few buildings within those walls. The first known example of a true concentric castle is Blaye Castle in France. It was built by Gaston IV, Count of Béarn on behalf of his wife Margaret of Navarre. The central tower is 128 feet high and the curtain wall around it is 20 feet thick.
These new castles changed the way people thought about defense. Before this time, defense just involved using up your resources quickly - if you ran out of food you died. But now that people knew for sure that attackers would be coming after their town or city, they needed defenses that could resist siege weapons for extended periods of time.
A siege was when an army tried to capture a town by blocking off its supplies. For example, soldiers might cut trees down to build a stockade out of in front of their gates or put rocks in front of their doors to make walking into the city too dangerous. They'd also try to find a weak point in the town's defenses to attack through. If the town didn't surrender, then eventually they'd run out of food and leave anyway.