A famous Yusuf’s Well, which goes down 97 meters to the level of the Nile is situated in the Citadel under a tower. Water seeps to the well from the river through natural channels. The great central shaft is surrounded by a spiral staircase that gives the well its local name Bir al-Halazun, "well of the snail".
The name Yusuf/Joseph was one of Salah el-Din’s. The well was dug during his time by Crusader prisoners. When in use, the rock stairs were covered with earth so that donkeys could carry the water up and down the ramp. Two aqueducts also supplied the Citadel, discharging water near the base of the hill that was then raised to the top by a series of water wheels.