Ferne Clyffe State Park is a nice little recreation area just south of Goreville IL on IL 37. The park encompasses 2,430 acres. There is fishing, hiking, Equestrian, and camping available at this park.
There is quite a bit to see in the park, but the two main attractions are Hawks cave, and the 100ft waterfall on Big Rocky Hollow trail (does not flow year round).
Full Review and info on best hiking Trails HERE