The
Sahara (, , 'the Greatest Desert') is the largest
hot desert and third largest
desert after
Antarctica and the
Arctic worldwide. Its surface area of —including the
Libyan Desert—is comparable to the respective land areas of
China or the
United States. The desert comprises much of the land found within
North Africa, excluding the fertile coastal region situated against the
Mediterranean Sea, the
Atlas Mountains of the
Maghreb, and the
Nile Valley of
Egypt and
Sudan. The Sahara stretches from the
Red Sea in the east and the
Mediterranean in the north, to the
Atlantic Ocean in the west, where the landscape gradually transitions to a coastal plain. To the south, it is delimited by the
Sahel, a belt of
semi-arid tropical savanna around the
Niger River valley and
Sudan Region of
Sub-Saharan Africa. The Sahara can be divided into several regions, including the western Sahara, the central
Ahaggar Mountains, the
Tibesti Mountains, the
Aïr Mountains, the
Ténéré desert, and the
Libyan Desert. Its name is derived from the plural
Arabic language word for desert ( ).
