The ensemble of preserved ruins known as the Al Qal'ah of Beni Hammad is situated on the southern flank of the Jebel Maâdid in a mountainous setting of striking beauty. It bears exceptional witness to a cultural tradition: it is one of the most interesting and most precisely dated monumental complexes of the Islamic civilization and provides an authentic picture of a fortified Muslim city.
In a mountainous site at 1,000 m above sea level, on the southern flank of the Jebel Maâdid, are to be found the ruins of the first capital of the Hammadid emirs, founded in 1007 by Hammad, son of Bologhine, the founder of Algiers. The city was abandoned in 1090 when it was menaced by a Hilalian invasion, and finally destroyed in 1152 by the Almohads. It enjoyed great splendour during the 11th century. The Al Qal'a encompasses a large number of monumental remains, among which are the Great Mosque and its minaret, as well as a series of palaces including the Kanar, Greeting and Lake Palaces.
The mosque, with its prayer room of 13 aisles with eight bays, is one of the largest in Algeria after that of Mansura. The minaret, 25 m high, is the prototype of the three-tiered minaret composition which may be seen most notably at the Giralda of Seville. The palatial ruins bear witness to the great refinement of the Hammadid civilization.
The Castle of the Beacon Light, set on a sheer rocky peak from which its keep dominated the surrounding area, was inspired by the layout of eastern palaces. The palace of the Hammadid emirs is a complex made up of three residences separated by gardens, pavilions and cisterns.
Excavations have brought to light the locations of other palaces, as well as an abundance of other material which is exhibited in the museums of Sétif, Constantine and Algiers.