Boulders shaped by the wind erosion at Wadi al-Hitan, the Whale Valley in the Sahara desert

Boulders at Wadi al-Hitan, the Valley of the Whales in the Sahara desert in Egypt, shaped by the wind erosion (aeolian processes). Wadi al-Hitan, the Whale Valley, is a UNESCO World Heritage Site, known for its great number of fossils, particularly those of the early forms of whales called Archaeoceti, the mammals which lived here in Eocene. They make Wadi al-Hitan a very significant site for the history of evolution.