Construction workers in South Dakota unearthed a mammoth treasure pit that shocked Ice Age scientists

A hidden pit held more than fossils

In 1974, workers building in Hot Springs, South Dakota uncovered a rare Ice Age fossil site: a natural pit packed with mammoth remains. What they exposed offered scientists a vivid snapshot of prehistoric North America—along with evidence of how these animals could become trapped. Decades later, the discovery remains one of the continent’s richest mammoth fossil localities.