St. Simons Island, GA! 2 hours, 17 minutes, 122.45 miles via I-95 S from Hilton Head Island. St. Simons Island is the largest of the Golden Isles along Georgia’s southern Atlantic coast. Eighteen square miles in size, St. Simons Island is accessible by car via the F.J. Torras Causeway. St. Simons has a wide array of lodging choices rounding out your choice for a spectacular St. Simons Island vacation.