In a moun­tain­ous 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.