Reef-Ringed Bora-Bora 
Lacy breakers lap the coral reef that rings Bora-Bora, an ancient sunken volcano 165 miles (266 kilometers) northwest of Tahiti in French Polynesia's Society Islands. Surrounded by sugar-white beaches, an electric-blue lagoon, and some of the clearest water on the planet, Bora-Bora is home to hundreds of species of tropical fish.
Blue Hole 
Approximately 60 miles (100 kilometers) from Belize City, the almost perfectly circular Blue Hole is more than 1,000 feet (300 meters) across and some 400 feet (120 meters) deep. The hole is the opening to what was a dry cave system during the Ice Age. When the ice melted and the sea level rose, the caves were flooded, creating what is now a magnet for intrepid divers.
Fiji Islands
A dramatic collar of coral reefs rings Mondriki Island, foreground, and Monu Island, background, two of Melanesia's Fiji Islands. The Fiji Islands are made up of 333 islands in the South Pacific, known for their sparkling beaches, coral gardens, and lush rain forests.
Palau Islands 
Located in the western Pacific, Palau is made up of more than 250 islands, such as these forested, sand-ringed gems studding sapphire seas. Tourism is the country's main industry; its rich marine environment invites snorkeling, diving, and lounging.
Aerial Bora-Bora 
Wreathed by coral reefs, Bora-Bora is the sunken remnant of an extinct volcano. The island's creamy blue lagoon is best appreciated from the air, where its contrast with surrounding waters is most apparent.
Glover Reef
A pair of rainbows arcs over Belize's Glover Reef in the Caribbean Sea. Boasting an incredibly rich variety of marine life and some of the best diving and snorkeling in the Caribbean, Glover Reef is a national marine reserve and was named a UNESCO World Heritage site in 1997.
Cape Hatteras National Seashore
Swirling sandbars wend their way across Oregon Inlet, part of Cape Hatteras National Seashore in North Carolina's Outer Banks. The Outer Banks—a 200-mile-long (322-kilometer-long) chain of low, slim barrier islands—arc out from the mainland, protecting the coast and shallow sounds from the battering Atlantic.
Bora-Bora Island 
Foaming waves lap the shores of Bora-Bora as twin peaks Mount Pahia and Mount Otemanu rise from an extinct volcano on the island. An overseas territory of France, Bora-Bora is in the Leeward group of French Polynesia's Society Islands in the Pacific Ocean.
Caribbean Sea, Belize
Surf frosts the sparkling surface of the Caribbean Sea off the coast of Belize in Central America. Sometimes called the American Mediterranean for its location between two continental landmasses, the 1,063,000-square-mile (2,753,000-square-kilometer) body of water is named after the Carib Indians, the dominant peoples in the region when Europeans arrived in the 15th century.
Tahiti
A mass of fluffy white clouds crowns the lush hills of the island of Tahiti. Tahiti and her 13 sister islands make up the Society Islands, tiny volcano- and coral-studded protrusions of land that dot the South Pacific about halfway between Australia and South America.
