Located in the Sahara Desert in southeastern Algeria, Tassili n'Ajjer houses one of the most essential groupings of prehistoric cave art in the world. In the national park, more than 15,000 drawings and engravings depict the climatic changes, the animal migrations and the evolution of human life in the Sahara from 6000 BC to the first centuries of the present era. It was listed as a UNESCO World Heritage Site in 1982.