In 1947 a well-preserved skull of a species of early man known as Plesianthropus trasvaalenssis was discovered. The skull became known as Mrs. Ples, dating back 2.5-million years. The total of over 700 hominid specimens found here has made Sterkfontein the world’s richest hominid site. A section of the caves is visited on an hour long guided tour and the excavation site can be viewed. A visit to the newly built Sterkfontein Orientation Centre is also included, displaying information about significant findings, as well as general information on human and cultural evolution.