Yes, the above-sea level view on St. John is something out of a honeymoon brochure. But you’d be missing half the point if you never stuck your head underwater on this reef-ringed island, home to sea turtles, neon-bright fish, and 50 species of coral (including seven that are threatened). Best plan: Basecamp at the forested Cinnamon Bay Campground just off the beach and see the best of both worlds on day trips. On dry land, hike the 2.2-mile (one-way) Reef Bay Trail, a mostly downhill path through lush kapok, bay rum, and spike-studded “monkey no climb” trees and past the remains of several 1700s Danish sugarcane plantations. (Don’t miss the .3-mile spur at mile 1.5 to a panel of petroglyphs left by the Taíno culture between 900 and 1400 AD.) Pop out of the forest at Reef Bay for a dip in the calm water, then backtrack. For a peek under the waves, link the Leinster Bay, Johnny Horn, and Brown Bay Trails for a 3-mile (one-way) hike past several primo snorkeling spots. At Leinster Bay and Watermelon Cay, look for cushion sea stars, turtles, and branching gorgonians (a coral relative); staghorn corals, conch, and fish are the stars at Brown Bay. With water temps a near-constant 80°F and underwater views stretching 60 feet and beyond, you might never want to dry off. Average January high/low 82°F/70°F Season Year-round Camping $37/primitive campsite, $67-$93/platform tent.