You’ll find some of the best snorkeling the entire country in the waters of Dry Tortugas National Park. Year-round the waters are clear, shallow and warm, opening up an undersea world of tropical fish, coral, sponges sea fans and others. And the best part is that it’s absolutely free. You can bring your own gear and go in from the beach near Fort Jefferson. Your tour provider may also have equipment available at no cost.

Massive Fort Jefferson, situated on Garden Key, was begun in 1846 but never completed. It was used for various purposes over the years but ceased operation as a military facility in the 1874. Today you can tour the fort and the moat around it on your own, or you can take a ranger-guided tour about the fort’s history and preservation efforts.

Loggerhead Key is the largest island in the park. The island is uninhabited and you’ll need to find a tour that will take you there, but it can be a peaceful respite from Garden Key. It is also home to the Loggerhead lighthouse, constructed in 1857. You won’t need to spend too much time on the island, but it’s got a wealth of scenery and great photo opportunities.