The prayer hall is characterized by its rectangular shape and the size of its proportions: 200 m long, 100 m wide and 60 m high. The built area reaches 20,000 m² and its capacity is about 25,000 faithful.
 
The prayer hall is also characterized by its removable roof, covering an area of 3,400 m², which is able to open in five minutes to transform the center of this room into a large patio. The channel of fresh water that crosses the latter evokes the Arab riads of Muslim Andalusia.
 
The roof is adorned with a series of 14 domes (8 hassani and 6 settini type), 5 sheaths, 4 beams and 50 Murano glass chandeliers of 6 m in diameter, 10 m in height and a weight of 1200 kg each.
 
The roof covering required the installation of 300,000 tiles made especially of cast aluminum by the Bouygues group (main contractor), imitating the traditional glazed terracotta tile from Fez but four times lighter.
 
For the finishing touches and the religious objects, craftsmen of all the kingdom contributed to cover more than 53.000 m² of carved wood and more than 10.000 m² of zellij representing 80 new patterns.
 
The large prayer hall is dominated by two mezzanines with a total area of 3,550 m², reserved for women and connected by four stairs to ablution rooms.