Note: Extensive underground caves on farm Swartkrans, noted for underground lake and stalagmites; around 3.5 million years ago, the area was a shelter for animals and had hazardous hidden openings into which one could fall; many animals and 600 hominid fossils have been found, including Australopithecus africanus, Homo habilis and others. Grouped with neighboring sites Swartkrans and Kromdraai, it is protected as part of a large World Heritage Site by UNESCO.