Size: 4,635 acres
Year Designated: 1976
Fast Fact: Critical sanctuary for bison as well as the threatened bald eagle.
Named after the frontier fort that once stood on the land in northern Nebraska, the Fort Niobrara Wilderness now offers protection to bison, bald eagle, prairie dogs, mule deer and river otters. The latter reside in the Niobrara River, which flows for nine miles through the area.