(Illinois)
Mississippi Palisades State Park is a National Natural Landmark located in Carroll County, Illinois, just north of the town of Savanna. It is a partially conserved section of the Mississippi Palisades. The area contains many caves and large cliffs along the Mississippi River at the mouth of the Apple River in the Driftless Area of far northwestern Illinois. (Ref: https://en.wikipedia.org/wiki/Mississippi_Palisades_State_Park)