Arkansas

Historical marker location:

4023 Columbia Avenue, Franklin, Tennessee

( Marker can be reached from Columbia Avenue (U.S. 31) south of Mack C Hatcher Memorial Parkway (Tennessee Route 397), on the right when traveling south.)

The largest underground lake in the United States is located in Tennessee. The Lost Sea, located in Sweetwater, Tennessee, covers over four acres and is home to a variety of unusual creatures, including blind fish and crayfish.