Because of the altitude and the water-retaining properties of the sandstone, the vegetation in the Tassili is somewhat richer than in the surrounding desert. This includes a very sparse tree population of the endangered, endemic Sahara cypress (Cupressus dupreziana) and the Sahara myrtle (Myrtus nivellei) in the higher altitudes in the east of the area. - Tassili n'Ajjer - Tin Abou Teka - Algeria - 1966
