Cumberland Island

“Accessible only by ferry and largely managed as the Cumberland Island National Seashore by the National Park Service, it features 17 miles of undeveloped beaches, wild roaming horses, maritime forests, and the historic ruins of the Carnegie family mansion, Dungeness. You can stay in the Goodbread House in St. Mary’s, splurge on the Greyfield in (the island’s only guest residence — $$$$ but 50% off Nov 30–Dec 21), or camp on the island if you’re well-insulated and scrappy!”