Agate Fossil Beds
United States
About Agate Fossil Beds
Agate Fossil Beds National Monument preserves one of the world's most important Miocene mammal fossil sites, dating back 19-23 million years. The monument protects fossils of ancient mammals including oreodonts, three-toed horses, and bear-dogs in their original geological context. The site also features the James Cook collection of Lakota artifacts and preserves the cultural history of the High Plains. Managed by the National Park Service, the monument offers visitors a glimpse into both prehistoric life and Native American heritage.