John Day Fossil Beds National Monument is a U.S. national monument in Wheeler and Grant counties in east-central Oregon. Located within the John Day River basin and managed by the National Park Service, the park is known for its well-preserved layers of fossil plants and mammals that lived in the region between the late Eocene, about 45 million years ago, and the late Miocene, about 5 million years ago. The monument consists of three geographically separate units: Sheep Rock, Painted Hills, and Clarno. The units cover a total of of semi-desert shrublands, riparian zones, and colorful badlands. About 210,000 people visited the park in 2016 to engage in outdoor recreation or to visit the Thomas Condon Paleontology Center or the James Cant Ranch Historic District. Before the arrival of Euro-Americans in the 19th century, the John Day basin was frequented by Sahaptin people who hunted, fished, and gathered roots and berries in the region. After road-building made the valley more accessible, settlers established farms, ranches, and a few small towns along the river and its tributaries. Paleontologists have been unearthing and studying the fossils in the region since 1864, when Thomas Condon, a missionary and amateur geologist, recognized their importance and made them known globally. Parts of the basin became a National Monument in 1975. Averaging about in elevation, the monument has a dry climate with temperatures that vary from summer highs of about to winter lows below freezing. The monument has more than 80 soil types that support a wide variety of flora, ranging from willow trees near the river to grasses on alluvial fans to cactus among rocks at higher elevations. Fauna include more than 50 species of resident and migratory birds. Large mammals like elk and smaller animals such as raccoons, coyotes, and voles frequent these units, which are also populated by a wide variety of reptiles, fish, butterflies, and other creatures adapted to particular niches of a mountainous semi-desert terrain. Geography The John Day Fossil Beds National Monument consists of three widely separated units—Sheep Rock, Painted Hills, and Clarno—in the John Day River basin of east-central Oregon. Located in rugged terrain in the counties of Wheeler and Grant, the park units are characterized by hills, deep ravines, and eroded fossil-bearing rock formations. To the west lies the Cascade Range, to the south the Ochoco Mountains, and to the east the Blue Mountains. Elevations within the park