In 1978, two young men discovered a bone eroding from the side of a ravine. They took the bone to the Strecker Museum at Baylor University, where it was identified as part of a Columbian mammoth (Mammuthus columbi). Museum staff members and volunteers quickly began excavations at the site. Between 1978 and 1997, the fossil remains of 22 Columbian mammoths, a camel (Camelops hesternus), and the tooth of a juvenile saber-tooth cat were discovered.
In 2006, plans were initiated to make the site a public park. With the combined support of the City of Waco, the Waco Mammoth Foundation, and Baylor University, this goal became a reality. The Waco Mammoth Site opened to the public in December 2009.
On July 10, 2015, President Barack Obama signed an Executive Order designating the Waco Mammoth National Monument as the 408th unit of the National Park System. As part of this designation, Baylor University’s Mayborn Museum Complex has become the official repository for the park. Under this agreement the Mayborn Museum Complex will continue to store and make accessible to research all of the paleontological and archaeological objects that have been removed from the park, as well as their associated documentation.