Cradle of Humankind
This site currently occupies 183 square miles (474 km²); it contains a complex of limestone caves, including the Sterkfontein Caves, which were the locale of the discovery of a 2.5 million year-old fossil Australopithecus africanus in 1936, thus corroborating the 1924 discovery of the Taung child by Raymond Dart. Other archaeological digs are on-going at this site. The use of fire at this site has been dated 1 million years BP at Swartkrans.
The fossils have been spared by time because they were washed into the caves, mixing with the limestone and other sediments to form breccia. The current thinking is that similar hominids lived all over Africa, but their evidence has been eroded away.