Tassili n’Ajjer Mountains in the Sahara Desert, Algeria25.5N 9.0E
Tassili n’Ajjer is a mountain range in the Sahara desert in southeast Algeria, North Africa. It extends about 500 km, and the highest point is Adrar Afao, at 2158 m. The nearest town is Djanet, about 10 km southwest of the range. Much of the range is protected in a National park, Biosphere Reserve and World Heritage Site, named the Tassili n’Ajjer National Park.
The range is composed largely of sandstone. Erosion in the area has resulted in nearly 300 natural rock arches being formed, along with many other spectacular landforms. Because of the altitude and the water-holding properties of the sandstone, the vegetation is somewhat richer than the surrounding desert; it includes a very scattered woodland of the endangered endemic species Saharan Cypress and Saharan Myrtle in the higher eastern half of the range.