In November 1981, members of the United States space shuttle Columbia returned with
radar images of the eastern Sahara Desert. The image had peeled back 30 feet of the
Selima Sand Sheet, a 39,000-square-mile plain, revealing the desert in its form 10 to
20 million years ago: as a land of flowing rivers, swamps, and lush savannas full of
The ancient rivers flowed longitudinally, perhaps even linking the Niger and Benue
Rivers with the Nile in the east. The images also revealed that water still flows
through some of the valleys beneath the sands.
Other evidence also confirms the Sahara’s history. A 300-foot-high petrified coral
reef exists across southern Morocco. A dinosaur graveyard has also been discovered
near Agadez in Niger. Petrified tree trunks are scattered through the deserts in
Algeria and Egypt. Humans only arrived in the area about 10,000 years ago, when the
waters were already drying up. However, Neolithic tools have been discovered along the
banks of the ancient waterways, including bone harpoons that settlers used to fish in
the long-forgotten lakes of the region.
More recent evidence has been found on a high sandstone plateau 5,000 feet above the
plains of southern Algeria, at Tassili-n-Ajjer in the heart of the desert. Here,
hundreds of cave paintings as old as 9,000 years, show men in loincloths rounding up
long-horned cattle, women with baskets on their heads, and archers pursuing antelope
The paintings, tracing the development of the people, show pictures of early wild
animals: buffalo, lions, antelopes, and elephants. Later images depict domesticated
animals, two-wheeled war chariots, Nile boats, and camels. The painters stopped about
2,000 years ago, leaving the area that was rapidly becoming desert. Even today, the
Sahara continues to expand, at a rate of more than three miles per year.