It was in the Sterkfontein Caves, in 1936, that Dr. Robert Broom discovered the now famous Mrs. Ples, as she is popularly known—a skull of an adult Australopithecus africanus that is more than 2 million years old. The find reinforced the discovery of a skull of an Australopithecus child, the Taung Skull, by Professor Raymond Dart in 1924, which was the first hominid ever found. At the time, Dart was ostracized for claiming the skull belonged to an early human ancestor. Scientists in Europe and the United States simply didn't believe that humanity could have originated in Africa. Today, few disagree with this theory. Another important find was the discovery in the 1990s of Little Foot, a near-complete skeleton of an Australopithecus, embedded in rock deep inside the caves. Guided tours of the excavations and caves, which are spacious and not claustrophobic, last an hour. Wear comfortable shoes. Spend some time in the small but excellent Sterkfontein Visitor Centre, which has exhibits depicting the origins of the earth, life, and humanity. A small on-site restaurant is open daily.