Mzab (əmzäbˈ) [key], stony, barren valley, Algeria, in the N Sahara. It was settled c.1000 by members of an austere Muslim sect, the Kharijites. The inhabitants, called Mozabites, dug wells, created date-palm oases, and built seven towns, united in a confederation. As traders, they made the area a caravan junction. France occupied the Mzab in 1853 and annexed it formally in 1882. It was transferred to Algeria in 1962. Water is pumped from more than 4,000 wells and 6 dams. Ghardaïa is the region's principal town.