Sub-Saharan Africa West and Central Africa), or sometimes extending from the coast of West Africa to Western Sudan. Its equivalent in Southeast Africa was "Zanj" ("Country of the Blacks"), which was situated in the vicinity of the Great Lakes region. The geographers drew an explicit ethnographic distinction between the Sudan region and its analogue Zanj, from the area to their extreme east on the Red Sea coast in the Horn of Africa. In modern-day Ethiopia and Eritrea was "Al-Habash" or Abyssinia, which was inhabited by the "Habash" or Abyssinians, who were the forebears of the Habesha. In northern Somalia was "Barbara" or
Horn of Africa single landmass around 18 million years ago, before the Gulf of Aden rifted and separated the Horn region from the Arabian Peninsula. The Somali Plate is bounded on the west by the East African Rift, which stretches south from the triple junction in the Afar Depression, and an undersea continuation of the rift extending southward offshore. The northern boundary is the Aden Ridge along the coast of Saudi Arabia. The eastern boundary is the Central Indian Ridge, the northern portion of which is also known as the Carlsberg Ridge. The southern boundary is the Southwest Indian Ridge. Extensive glaciers once