 These are the Clarens Formation laid down under desert conditions about 200 million years ago, topped by a thick layer of lava that erupted, and covered most of southern Africa, and indeed large parts of Gondwana, approximately 180 million years ago.These rocks form the steep sides of the Great Escarpment in this region, where its upper edge reaches an altitude in excess of .The erosional retreat of the escarpment from the coastline to their present position, approximately inland from their original position, means that the rocks that are exposed on coastal plain are, almost without exception, older than the rocks that cap the adjacent escarpment.