Even though there were a big amount of advantages for Stone Castles still remained a number of weaknesses within the design of these castles. Stone keeps are square and an attacker could, if they were fortunate enough to get close enough, mine underneath a corner and wait for the weight of the castle to bring the walls caving in. Likewise the defenders would need to have a large supply of food: there was nothing to stop a besieging force simply surrounding the Castle and waiting for them to starve!