Which desert covers most of northern Africa?

The Sahara Desert covers most of northern Africa and is the continent’s defining arid region.

Stretching from the Atlantic Ocean in the west to the Red Sea in the east, the Sahara occupies about 9.2 million square kilometers. It reaches north toward the Mediterranean and south to the Sahel, a semi-arid transition zone. The desert spans parts of Algeria, Chad, Egypt, Libya, Mali, Mauritania, Morocco, Niger, Sudan, Tunisia, and Western Sahara.

Despite its popular image, the Sahara is not simply an ocean of sand. Sand seas, called ergs, occupy only part of it. The landscape also includes rocky plateaus, gravel plains, dry river valleys, salt flats, mountains, and occasional oases. Rainfall is extremely low and irregular, but some areas support plants, wildlife, and human communities.

The name comes from the Arabic ṣaḥrāʾ, meaning “desert.” Another common mistake is calling the Sahara the world’s largest desert overall: Antarctica and the Arctic are larger, but the Sahara is the largest hot desert.