The Hammadids, for their part, built an entirely new fortified capital at Qal'at Bani Hammad, founded in 1007. Although abandoned and destroyed in the 12th century, the city has been studied by modern archeologists and is one of the best-preserved medieval Islamic capitals in the world. The Zirid branch in Granada was also responsible for turning it into one of the major cities of al-Andalus. Among the surviving remains of the Zirid period in Granada today are a section of its original city walls, an extensive system of cisterns on the Albaicín hill, and the former minaret of a mosque (now part of the Church of San José).
