Algeria’s Tassili N’Ajjer plateau is Africa’s largest national park. Among its vast sandstone formations is perhaps the world’s largest art museum. Curiously, however, these images do not depict the arid, barren landscape that is present in the Tassili N’Ajjer today. This rock art is an important record of the past environmental conditions that prevailed in the Sahara, the world’s largest hot desert. These images depict a period approximately 6,000-11,000 years ago called the Green Sahara or North African Humid Period.
