The Afar Triangle (also called the Afar Depression or the Danakil Depression) is a geological depression that is caused by the Afar Triple Junction which is part of the Great Rift Valley. It overlaps Eritrea, Djibouti and the entire Afar Region of Ethiopia. The Afar Triangle includes the Danakil Depression and the lowest point in Africa, Lake Asal (155 metres or 509 feet below sea level). Only the Awash River flows into the area, where it ends in a chain of lakes that increase in salinity. Dallol is also part of the depression, one of the hottest places year-round anywhere on Earth. The climate varies from around 25 °C (77 °F) during the rainy season (September–March) to 48 °C (118 °F) during the dry season (March–September).

Afar is well known as one of the cradles of hominids, containing the Middle Awash, site of many fossil hominid discoveries such as Ardi, (Ardipithecus ramidus); the Gona (Gawis cranium), site of the world's oldest stone tools; and Hadar, site of Lucy, the fossilized specimen of Australopithecus afarensis.