The weapons and techniques used throughout most of siege warfare are remarkably consistent with few innovations. The notable new weapons were the trebuchet, Greek fire, and Cannons.
           Siege towers or belfries were common if unwieldy weapons used at sieges throughout the medieval period. They were often made of wood and were built taller than the walls they would be used to assault. Sometimes towers were wheeled or they could also be built on sleds so that they could be pushed up against the walls. The most difficult part of using a tower was getting it up to the walls in the first place as most towns and castles were protected by ditches or moats. These would have to filled in and leveled out before a tower could be moved into position.