Fossil Butte National Monument

Fossil Butte National Monument is a unit of the National Park Service located 15 miles west of Kemmerer, Wyoming; the national monument was established on October 23, 1972. The site preserves the best paleontological record of Tertiary aquatic communities in North America and possibly the world, within the 50-million-year-old Green River lake beds. Fossils preserved, including fish, alligators, bats, turtles, dog-sized horses, insects, and many other species of plants and animals suggest that the region was a low, subtropical, freshwater basin when the sediments accumulated, over about a 2 million-year period. Coal mining for the railroad led to the settlement of the nearby town of Fossil, Wyoming, now a ghost town. When the fossils...