• The Agate Fossil Hills where mammal fossils were excavated in the early 1900's

    Agate Fossil Beds

    National Monument Nebraska

There are park alerts in effect.
show Alerts »
  • Park phone lines intermittently out of service

    If you cannot reach the park by phone, please click the Contact Us link on the left side of this page to email a ranger. Staff will call or email back during business hours.

Natural Features & Ecosystems

Across wetlands to the Fossil Hills

Looking across the wetlands of the Niobrara River to the Fossil Hills.

Agate Fossil Beds National Monument is a small park in the northwest corner of Nebraska, with only 2,700 acres of federally managed land included in the 3050 acres within the park boundary. The park takes its name from thin lenses of agate (White River Silicate Group) in the area, which range in color from amber to light gray. Miocene-age rocks are exposed in the park in the bluffs above the Niobrara River wetlands and contain an excellent fossil record. Much of the geologic history is recorded in the natural features found at the park today.

Did You Know?

Windmill head, typically on a 10-12 foot tower.

The windmills seen in the area are still used to pump water into stock tanks for cattle to drink. Some of these wells are 250 to 300 feet deep and provide a good source of water as long as the wind blows.