Cave-in-Rock State Park is located on the Ohio River in Hardin County, Illinois. To reach the park from the northern parts of Illinois, proceed south on I-57 exiting at Marion, IL, on highway 13 east. Go east through Marion and Harrisburg to the intersection of Illinois 1 and 13. Turn south 22 miles on highway 1 to Cave-in-Rock State Park. From the south, take highway 90 from Marion, KY., and cross the Cave-in-Rock ferry and follow directional signs to the park entrance. From the southeast take I-24 west from the I-24 bridge to exit #16, then go 38 miles east on Illinois highway 146 to the park. From Southern Indiana, proceed through Evansville, IN traveling West on highway 62 and Illinois highway 141 to Illinois Rt. 1, then go south 36 miles to Cave-in-Rock State Park.