To make up for all that driving on the last leg of the journey, the next stop on the road trip is nice and close -- it's just a short hop to The Mammoth Site located at Hot Springs, also in South Dakota.
Here, 26,000 years ago, woolly mammoths used to drink at a spring-fed pond -- until they became trapped in a sinkhole and died.
Today, The Mammoth Site is the world's largest mammoth research facility. By following walkways through the enclosed, air-conditioned facility, visitors are able to see mammoth bones that are still in situ in the Earth. The facility also offers visitors the chance to visit a working paleontology lab and an active dig site, in addition to viewing striking reconstructions of both mammoths and other ice age mammals.