The area is of outstanding universal value due to the complex of palaeo-anthropological sites which have yielded valuable evidence of the evolution of modern humns over the past 3.5 million years, on their way of life, and on the animals with which they lived and on which they fed. The landscape also preserves many features of that of prehistoric man. The Sterkfontein Caves are one of the richest and most productive palaeo-anthropological sites in the world. Amongst the findings are the first complete Australopithecus skull to be discovered and a 4.17 million-year-old almost complete ape-man skeleton.