Camp Grounds, Kentucky is halfway between Orland Park & Hilton Head Island
Corinth, NC is the halfway point.
Johnson city.
Elkin NC
Ashville, NC
Kingsland, GA
Prince George, VA
Enfield, NC
The closest town to the midpoint is Kuttawa, Kentucky.
Walterboro, SC
A reasonable halfway point would be Chattanooga, TN
South Carolina and Georgia share a border. The beaches of Hilton Head and Tybee Island are near there.