Fossil Butte National Monument Located in Kemmerer, WY TRAVEL BASICS - CAMPING - LODGING ACTIVITIES - FACILITIES - FEES/PERMITS (NPS Photo) IN BRIEF This 50-million year old lake bed is one of the richest fossil localities in the world. Recorded in limestone are dynamic and complete paleoecosystems that spanned two million years. Preservation is so complete that it allows for detailed study of ...

Localities of the Eocene: The Green River Formation One of the most important fossil sites for understanding the Eocene is found at Green River, located in western Colorado, eastern Utah and southwestern Wyoming in the United States. During the Eocene, this region was located at much the same latitude it is today, though global climate was more equable. Therefore, the climate in which the ...