Agate Fossil Beds National Monument Park

Paleontological site preserving Miocene mammal fossil beds

Agate Fossil Beds National Monument protects Miocene mammal fossil sites in western Nebraska; the visitor center interprets fossil deposits and guided trails cross prairie overlooking badland exposures.

Main image

Agate Fossil Beds National Monument at a Glance#

Address: Agate Fossil Beds National Monument - near Harrison, Nebraska, USA

Website: https://www.nps.gov/agfo

Admission: Free (National Park Service site)

About 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.

Tips for Visiting Agate Fossil Beds National Monument#

  • Visit in the cooler morning hours in spring or fall for more comfortable exploration of the open prairie and the short interpretive trails; summer heat can be intense and afternoons busier.
  • Check the National Park Service site for seasonal visitor center hours and ranger-led programs - the site is remote and programming/closures change by season, so confirming ahead avoids wasted travel.
  • Allow extra travel time and plan logistics carefully: services in the surrounding area are limited, so confirm fuel, food, and lodging options in advance rather than assuming local availability.

Best Time to Visit Agate Fossil Beds National Monument#

Best visited in late spring or early autumn for mild weather and comfortable outdoor exploration of the site.

Summer (Hot)
June-August · 15-35°C
High temperatures and the possibility of thunderstorms make summer hotter and more strenuous for outdoor exploration.
Spring (One of the best times)
March-May · 0-20°C
Mild temperatures and flowering grasslands make spring a comfortable time for hiking and viewing the outdoor fossil localities.
Autumn (Also very good)
September-November · 0-20°C
Cooler, drier conditions and fewer visitors than summer-good for outdoor trails and interpretive sites.
Winter (Cold)
December-February · -15-5°C
Cold, potentially snowy conditions make outdoor exploration less comfortable; plan accordingly.

Weather & Climate near Agate Fossil Beds National Monument#

Climate

Agate Fossil Beds National Monument's climate is classified as Cold Semi-Arid - Cold Semi-Arid climate with warm summers (peaking in July) and freezing winters (coldest in January). Temperatures range from -13°C to 32°C. Semi-arid with limited rainfall.

Air Quality: AQI 20 Good
Temperature & Rainfall
Temperature Range
32°
Warmest Month
-13°
Coldest Month
Monthly Conditions
Month Comfort Temp Feels Rain Sky Humidity Wind UV Daylight
January - -13° - 2° -11° 9 mm - - 4.7 m/s - -
February - -10° - 6° -7° 9 mm - - 4.7 m/s - -
March - -6° - 10° -3° 20 mm - - 5.0 m/s - -
April - -2° - 15° 4° 36 mm - - 5.1 m/s - -
May - 4° - 21° 13° 73 mm - - 4.9 m/s - -
June - 9° - 27° 18° 63 mm - - 4.5 m/s - -
July - 12° - 32° 22° 50 mm - - 4.1 m/s - -
August - 11° - 31° 21° 35 mm - - 4.0 m/s - -
September - 6° - 26° 16° 32 mm - - 4.1 m/s - -
October - -1° - 18° 6° 20 mm - - 4.3 m/s - -
November - -7° - 9° -4° 10 mm - - 4.4 m/s - -
December - -12° - 4° -10° 9 mm - - 4.5 m/s - -