Sterkfontein (Afrikaans for strong fountain) is a set of limestone caves of special interest to paleo-anthropologists located Northeast of Johannesburg, South Africa near the town of Krugersdorp.

A number of early hominid remains have been found at the site over the last few dacades.

Sterkfontein was declared a World Heritage Site in 2000 and is sometimes referred to as the cradle of humanity.

Modern excavation of the caves began in the late 1890s by limestone prospectors who noticed the fossils and eventually brought them to the attention of scientists. It was not until 1936 that students of Professor Raymond Dart and Dr. Robert Broom from Witwatersrand University began concerted excavations.

These excavations revealed many early hominids. In 1936, the Sterkfontein caves yielded the first adult Australopithecine, substantially strengthening Raymond Dart's claim that the skull known as the Taung child (Australopithecus africanus) was a human ancestor. There was a pause in excavation during World War II, but after the war Dr. Broom continued excavations. In 1947 he found the almost complete skull of an adult female Australopithecus africanus (or possibly that of an adolescent male). Broom initially named the skull Plesianthropus transvaalensis (near-man from Transvaal), but it became better known for the abbreviation Mrs. Ples. Mrs. Ples is estimated to be between 2.6 and 2.8 million years old.

Excavations continue to this day and finds now total some 500 hominids, making Sterkfontein the richest site in the world for early hominids.