Motte and Bailey
Stone Keep
Concentric
Developed in the 12th - 13th century, Concentric Castles offered the best defense yet, because of it's wall system. It contained an inner and outer wall. They were both made of stone and were equally thick, but the inner one was higher. That way, arrows that went over the first wall just bounced off the inner one. |
Another important change in castles was the switch from square to round towers. Round ones were much stronger and gave a larger view than the square towers. Also, the corners at the foundation of the square towers could be dug under by enemies, causing the entire thing to collapse. Round towers solved that problem.