The history of the citadel began in 1076 when the Saljukid prince Atsiz Ibn Uvak started the construction of a citadel, which was continued by prince Tutush Ibn Alb Arslan in 1095 AD. The second phase of the construction began with al-Malik Abu Bakr al-Adil in 1202, when he built a new citadel to replace the Saljukid one. However, he did not demolish the older citadel; rather, he built the new defenses in front of the old one to avoid the risk of being caught with half-built defenses. During the Mamlouk period restoration works were implemented in many parts of the citadel after Hulegu attack in 1260 AD, and after Tamerlane catastrophe in 1400 AD. The defensive role of the citadel declined during the Ottoman period, and was turned into a barrack.
The citadel in its present state is composed of 13 towers connected with curtain walls. It has a quasi-rectangular shape that prolongates east- west, with an area of about 3.3 hectares, which is the largest built area in the old city. The East side measures 165m, and the south side 240m, and they are perpendicular as are the east and north sides, before the north side bends abruptly after about two thirds of its length to meet the west side to fit with the river course, which borders the citadel on the North. The citadel has three types of towers: rectangular, square, and L-Shaped.