The Sous or Souss (Berber tamazirt n Sus, Arabic بلاد السوس bilā as-Sūs) is a region in southern Morocco. Geologically, it is the alluvial basin of the Oued Sous (asif n Sus), separated from the Sahara by the Anti-Atlas mountains. The natural vegetation in the Sous is savanna dominated by the Argan (Argania spinosa), a local endemic tree found nowhere else; part of the area is now a UNESCO Biosphere Reserve to protect this unique habitat.