This 11,480-acre natural area located in southern Illinois' Johnson County has three dedicated nature preserves-Heron Pond, Wildcat Bluff, and Little Black Slough Natural Area, found east of Highway 37 on the Lower Cache River unit. Nationally significant for the southern swamps found here at the northern portion of their range, the area contains 56 state threatened or endangered plant and animal species and several state champion trees. Visitors enjoy birding, hunting, wildlife watching, and hiking.