Cumberland Island’s chief attraction is its 17.5-mile white, sandy shoreline, the longest stretch of undeveloped beach in the country and a bird-watcher’s and shell collector’s paradise. In the island’s interior, hiking trails lead to inland swamps, palmetto stands, marshland, forests, and meadows, all teaming with wildlife. The Ice House Museum, operated by the National Park Service, contains artifacts and photos documenting the island’s history from Native American times through the Carnegie Era. To see more of what island life was like during the Gilded Age, guests can visit two former Carnegie estates: the 1898 Greek Revival-style Plum Orchard Mansion (limited hours) and the fire-damaged ruins of Dungenness Mansion, a 59-room turreted Scottish castle. Among the historic sites associated with the island’s former African-American community are the chimneys of slave cabins at the old Stafford plantation and the remains of Half Moon Bluff, a village settled by former slaves in the 1890s. The settlement’s tiny first African Baptist Church hosted John F. Kennedy Jr.’s secret wedding to Carolyn Bessette.