The kasbah enclosure is surrounded and protected by imposing thick walls, much of which still survives today. The walls, like those of the palaces and of most Moroccan city walls, were made of pisé or rammed earth.[1] They were around 7 meters thick on average, which was remarkable even for the time.[2][3] The walls were crowned along their length by typical pointed merlons which sheltered a "chemin de ronde" or wall walk, and reinforced at intervals by square bastion towers.[19][4] Behind the walls were ring roads and passages that allowed for troops within the kasbah to be deployed along the walls easily.[19]