Atar is a department of the Adrar Region in western Mauritania. The capital lies at Atar. The other villages in the department are Agui, Anguenni, Azougui, Choum, Ksar Trchane, Tachot, and TaÏzent.
Coordinates: 20°31′N 13°03′W / 20.517°N 13.050°W / 20.517; -13.050