The least visited national park in Florida is Dry Tortugas National Park, located roughly 70 miles west of Key West. Because it is accessible only by boat or seaplane, its annual visitor count typically hovers around 60,000 to 80,000 people—a fraction of the millions who flock to the Everglades. The park is a high-fidelity hidden gem consisting of seven small islands and the massive, 19th-century Fort Jefferson, which is the largest brick structure in the Americas. Visitors go there for world-class snorkeling in pristine coral reefs, birdwatching, and a sense of absolute isolation. Due to the limited capacity of the daily ferry (Yankee Freedom) and seaplane transfers, the park feels exclusive and uncrowded. If you plan to visit in 2026, booking several months in advance is a high-fidelity requirement, especially if you intend to secure one of the very few primitive camping permits available on Garden Key.