On top of Al-Habis, from where you have a fine view over the entire central Petra basin, Al-Habis Crusader Fortress is located. It is a secondary fortress, designed and sited to control the strategic communication route within the Petra basin that was not in sight of Al-Wu'eira Fortress.
To reach the fortress, head toward the blue "Habis Crusader Fortress" sign along the south-east base of Al-Habis, from there a rebuilt staircase follows the original crusader way up to the entrance of the fortress. Then you step up onto the open forecourt area, a terrace like projection along the south side of the Al-Habis, which is the lowest level of the fortress and it has four main parts to it: the observation tower at the summit; the upper ward surrounding it; the lower ward; and the forecourt.
Keep climbing up, and you will come to a doorway, whose threshold still shows the semicircular grooves made by the swinging door, then at the end of the stairs you reach a modern wooden blank bridge, then you pass through another doorway into the lower ward. On your left from there you find the stairs to the upper ward. At the summit of the upper ward you find the observation tower of the castle which takes the shape of a square.