These two kilils of northeastern Ethiopia are quite different. Tigray, at the top of the nation, is in the high plateau, with its eastern frontier coinciding with a steep escarpment. Tigray's northeast is also high but the land falls off toward the Sudanese border.
Afar, on the other hand, is low desert; in fact the Denkali (or Afar) Depression on the Eritrean border drops more than 100 meters below sea level. The volcanoes in this depression show it to be a contnental rip: a rift valley.
Tigray's west is drained by tributaries of the Atbara, part of the Nile system. The east drains into the valley. Southern Afar's eastern edge is the Awash river which flows north into the kilil's center to end at lakes Tehiyo, Gemeri and Abbe. These lakes, on or near the Djibouti border, are in the rift valley.
About seven in ten speak Tigrinya and most of the rest Afar. It is probable but uncertain that a majority are Ethiopian Orthodox Christians; the rest--including all the Afars--are Sunni Moslems. Most Moslems are bilingual in a form of Arabic.
The largest city is Mekele with only about 150,000 residents It is the capital of Tigray, high in the mounatins on the plateau's edge.
Later, according to the theory of Chistopher Ehret, speakers of Boreafrasian languages--a hypothesized one-time branch of the Afro-Asiatic group--passed through the area and spread far westward and northward. This group gave rise to the Semitic languages far outside the area. These spread to southern Arabia. About 2000 years ago, one group of South Arabian Semites moved en masse across the Red Sea to the Eritrean coast. These spoke Ethiopic, the ancestor of Tigrinya and other languages. They gradually pentrated westward into this area.
In the fourth century a king of Axum, the kingdom centered in the town of that name northwest of Mekele, converted to Coptic Christianity. Islam entered a few centuries later and converted the lowlanders and a minority of the highlanders.
north and east
southeast
south of Afar
south of Tigray and west of Afar
northwest
(1)Ityopia officially.
(2) Also spelled Affar.