The present maqsura and mihrab were built during the extension of the second Al-Haken. The maqsura, the area reserved for the caliph, is a rectangular area attached to the quibla wall. It is surrounded and divided into three by colonnades of criss-crossing polybullous arches. In the wall of the eastern space is the doorway of the now-defunct Treasure Room or Bayt al-mal. In the western wall is the Sabbath Gate, through which the caliph used to enter through a passageway that led directly to the citadel. In the central space is the Mihrab Gate, which consists of a richly decorated horseshoe arch that leads to the mihrab chamber.

The mihrab chamber, which is embedded in the quibla wall, is octagonal in plan with a shell-shaped dome. The walls are decorated with a marble plinth and six polybullous arches on six sides of the plinth.