A high volcanic massif rising abruptly from the lowlands of Eritrea, Ethiopia, Djibouti, and Somalia. Plateaus, cliffs, deep valleys, and isolated basins create natural fortresses and distinct cultural zones. Reliable highland rainfall supports ancient agriculture, while the Red Sea coast provides maritime gateways. Geography produces resilient, mountain-anchored civilizations—semiautonomous, literate early, and internally cohesive. This region forms a cultural sphere separate from both the Sahara and sub-Saharan Africa.
