Lake Ilo National Wildlife Refuge in western North Dakota combines prairie, wetlands, and a man-made lake that supports abundant wildlife while preserving an exceptionally long human history. People lived in this region for about 11,000 years, and archaeological work beginning in 1989 uncovered more than 58,000 Folsom-period stone artifacts, along with a tipi ring and bones from extinct mammals. The modern lake emerged from a federal dam project begun in 1936 and led to the refuge’s creation in 1939. Today, its grasslands, lake, and smaller wetlands provide habitat for hundreds of bird species, large migrations of waterfowl, and many mammals, fish, amphibians, and reptiles.