Site north of Bamako, Mali, which may have been the capital of the ancient Ghana empire in the 11th century. Ghana was a great trading empire that flourished in western Africa from the 9th through the 13th century. The city had a large urban settlement, two cemeteries, and a mosque. Within its boundaries there were--as was the custom of the early kingdoms of the western Sudan - two cities, one of which was occupied by the king, the other by Muslim traders. The mosque's foundation was built in the 9th century AD. Ghana's power declined during the 11th century after nearly 20 years of attacks from the Almoravids, a Berber military and religious order from the Sahara, devoted to converting nonbelievers to Islam.