While there's plenty to so in Charlotte Amalie on land, it would be a great loss not to explore the underwater wonders of the U.S. Virgin Islands. The easiest thing to do is rent a snorkel and explore the shallow waters by the beach, but you should definitely consider trying something more advanced at least once. Snorkelling is the cheapest choice. Add some diving equipment to go deeper and see more. Some tours now offer Sea Trek helmets — a modern take on the diving helmet.
No matter your choice of equipment, do explore the coral reefs that are home to tropical fish such as snapper, hamlets, parrot fish, sturgeon, squirrel fish and majestic sea turtles.