Dry Tortugas National Park

No visit to the Florida Keys would be complete without exploring the Dry Tortugas National Park. It preserves Fort Jefferson – an unfinished 19th-century fort that is currently the largest brick masonry structure in the western hemisphere – and the surrounding subtropical islands. There’s something here for every taste: hiking, ranger days, Fort Jefferson tours, snorkeling and birding, to name a few. Keep your eyes peeled for the sea turtles that give the park its name – there are five species to spot), but remember to keep your distance. Recommended by local insider Alli Griffiths