Al Qal'a of Beni Hammad (Arabic: قلعة بني حماد) in Algeria located close to the Algerian coast west of Algiers.
The site of extraordinary beauty, the ruins of the first capital of the Hammadid emirs, founded in 1007 and demolished in 1152, provide an authentic picture of a fortified Muslim city. The mosque, whose prayer room has 13 aisles with eight bays, is one of the largest in Algeria.