Agate Fossil Beds National Monument

Agate Fossil Beds National Monument in northwest Nebraska protects Miocene fossil beds that preserve mammals from roughly 20 million years ago. The monument conserves fossil localities and presents interpretive exhibits about the paleontology and geology of the region.

On-site exhibits and a visitor center explain the scientific significance of the faunal assemblages, and short trails lead to protected fossil localities and outcrops. The fossils include early horses, rhinoceroses and other mammals that document North American ecosystems during the Miocene.

The fossil localities were discovered and studied by late 19th- and early 20th-century paleontologists; collected specimens are held in research collections and the monument interprets the discoveries for the public. Protection of the sites has allowed scientific study alongside public education.

The monument is located near the town of Harrison in Sheridan County, in Nebraska’s northwest, set within mixed-grass prairie and rolling buttes.

• Miocene fossil assemblage: Fossils preserved at the site date to the Miocene, roughly 20 million years ago, and include a range of mammals important for understanding North American faunas of that epoch.
• Visitor facilities and location: The visitor center and short trails interpret the fossil sites; the monument lies near the town of Harrison in northwest Nebraska and is managed by the U.S. National Park Service.