This fascinating uninhabited island has been called the most important attraction in the Caribbean for its ties to history and its abundant marine life, including sea turtles. Buck Island is actually the only underwater national park in the world, and features a marked underwater trail. Snorkelers or divers can see vivid elkhorn coral reefs, 250 species of tropical fish, marine plants, and rock grottoes. Above the surface, the white sand Turtle Beach is one of the finest in the world. In the spring endangered Leatherback turtles nest on the beach, while Green turtles and Hawksbill turtles nest during the summer months. Picnic tables, barbecue pits, and bathroom facilities are available, but not much else. Many tour companies offer charters to the island, and some provide snorkeling gear as well.