Arrow slit in the walls and towers was distributed to minimize the amount of dead ground around the castle . Machicolations crowned the walls , offering defenders a way to hurl projectiles towards enemies at the foot of the wall . They was so cramped archers would have had to crouch inside them . The box machicolations was unusual : those at Krak des Chevaliers was more complex that those at Saône or Margat and there was no comparable features amongst Crusader castles . However , they bore similarities to Muslim work , such as the contemporary defences at the Citadel of Aleppo . It is unclear which side imitated the other , as the date they was added to Krak des Chevaliers is unknown , but it do provide evidence for the diffusion of military ideas between the Muslim and Christian armies . These defences was accessed by a wall @-@ walk known as a chemin de ronde . In the opinion of historian Hugh Kennedy the defences of the outer wall was " the most elaborate and developed anywhere in the Latin east ... the whole structure is a brilliantly designed and superbly built fighting machine " .