Sterkfontein, the Cradle of Humankind

Sterkfontein means strong spring in Afrikaans, and it is a set of limestone caves about 40 km northwest of Johannesburg that has done more to establish where humans come from than almost any other site on Earth.

The excavation began by accident. Limestone miners working the caves in the late 1890s noticed fossils in the rock and brought them to the attention of scientists. Proper work started in 1936, when students of Professor Raymond Dart and Dr Robert Broom of the University of the Witwatersrand began concerted excavation.

What they pulled out settled an argument. Dart had claimed that the Taung Child, an Australopithecus africanus skull, was a human ancestor, and had been widely doubted. Sterkfontein produced the first adult australopithecine, which substantially strengthened his case. Decades of work since have yielded hominin remains attributed to Australopithecus, early Homo and Paranthropus.

The caves are a South African National Heritage Site and were declared a World Heritage Site in 2000. The area around them, taking in the nearby archaeological sites of Swartkrans and Kromdraai, is known as the Cradle of Humankind.

It is not only fossils down there. The caves host a large nesting population of Belonogaster petiolata, a wasp, which is a reminder that the place is a living cave rather than a museum case.

Access has been interrupted recently: the owner closed the caves to visitors in 2024 because of flooding, and they reopened on 15 April 2025.

Two finds stand out. In 1947 Broom recovered a nearly complete adult skull, STS 5, which he first named Plesianthropus transvaalensis, near-man from the Transvaal, and which the world knows as Mrs Ples. It is now classified as Australopithecus africanus and dated to between 2.05 and 2.01 million years. Then in 1997 Ronald Clarke found a nearly complete skeleton of a second Australopithecus species, StW 573, nicknamed Little Foot because the first pieces identified, in 1995, were foot bones that had been sitting in storage. Extracting it from the surrounding breccia is still going on.

Finds here now total around 500 hominids, which makes Sterkfontein one of the richest early hominid sites on Earth. Over 90 percent of the research is funded by the Palaeo-Anthropology Scientific Trust, set up in 1993, which was also instrumental in the World Heritage nomination.