The development of the region's economy allowed civilizations to form, beginning with the Nok culture in 1000 B.C. and the Ghana Empire which first flourished between the 1st and 3rd centuries which later gave way to the Mali Empire. In current day Mauritania, there exists archaeological sites in the towns of Tichit and Oualata that were initially constructed around 2000 B.C., and was found to have originated from the Soninke branch of the Mandé peoples. Also, based on the archaeology of city of Kumbi Saleh in modern-day Mauritania, the Mali empire came to dominate much of the region until its defeat by Almoravid invaders in 1052. The Mali Empire flourished for several centuries.