Castles – card sort The keep was made of wood The keep was on a mound, called a motte. A wooden bridge connected the keep with the bailey. It was surrounded by a wooden palisade. It took about 14 days to build. Some of them were brought across from Normandy in ready to assemble pieces. It could catch fire very easily. It was liable to rot. It’s walls could be up to 6 metres thick. The walls often had narrow arrow slits. The walls were topped with crenulations. They were built of stone. The gatehouse often had murder holes. There was a drawbridge and a portcullis. The enemy often tried to undermine the walls by digging deep beneath them. Dover, Windsor and the Tower of London are all examples of them. Maurice the Engineer designed them. The keep could be up to 30 metres high. They often contained a private chapel. They were built immediately after the Norman invasion.