A reasonable halfway point would be Chattanooga, TN
From Saint Louis, Missouri to Hilton Head Island, South Carolina it is 838 miles.
Hilton Head is in South Carolina, about 40 miles from Savannah.
It is 380.13 miles accordig to MapQuest.
Charleston, South Carolina is 98 miles away from Hilton Head Island, South Carolina. It would about 2 hours to drive by car.
According to google maps, the trip to from Hilton Head Island to Charleston, SC is a 2 and a half hour drive.
The driving distance between Tulsa, OK and Hilton Head Island, SC is 1,064 miles.
About 600 miles
Too far. Stay home, yankee.
The halfway point falls in Hamptonville, North Carolina.
It is 31.4 miles according to Google Maps.
The closest town to the midpoint is Kuttawa, Kentucky.
It is 446 miles according to Google Maps.