Maropeng: Official Visitor Centre for the Cradle of Humankind World Heritage site

This guide to Maropeng, visitor centre for the Cradle of Humankind near Johannesburg, opens in 1994 with paleontologist Ron Clarke sifting through boxes of old mining debris and finding four small foot bones that didn't belong to any animal. It follows the search his colleagues made through the nearby caves for the rest of the skeleton, and the years spent freeing it from stone as hard as concrete. Listen for what waits at the end of the underground boat ride.