The Danakil Depression is the northern part of the Afar Triangle or Afar Depression in Ethiopia, a geological depression that has resulted from the divergence of three tectonic plates in the Horn of Africa.

The Danakil Depression is a vast plain, some 200 by 50 km (124 by 31 mi), lying in the north of the Afar Region of Ethiopia, near the border with Eritrea. It is about 125 m (410 ft) below sea level and is bordered to the west by the Ethiopian Plateau and to the east by the Danakil Alps, beyond which is the Red Sea.

The area is often referred to as the cradle of humanity; in 1974 Donald Johanson and his colleagues found the famous Australopithecus fossil Lucy, which has been dated 3.2 million years old and many other fossils of ancient hominins have been uncovered here, prompting many palaeontologists to propose that this area is where the human species first evolved.

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