Belize’s largest and possibly most beautiful island was plucked straight from a tropical dream. Located next to the largest barrier reef in the Western Hemisphere, Ambergris Caye’s crystal clear blue waters are perfect for exploring by scuba diving or kayaking.

There are plenty of diving locations at Bohol Island with plenty to see. Divers who explore Bohol Island, the 10th largest island in the Philippines, will swim among tuna, snappers, groupers, mackerel and surgeonfish and view schools of dolphins and pilot whales.

Bonaire is the perfect escape from the stressors of work or loud city life. Peace and relaxation are key on this island, and visitors are known to adapt to the unhurried style of each day. Bonaire is an award-winning diving destination with more than 60 dive sites for all levels. When exploring the waters, swimmers and snorkelers will be greeted by over 350 species of fish and more than 50 species of coral, a gorgeous sight.

There are a myriad of activities that can be enjoyed at Buck Island — like hiking or bird watching — but none compare to the swimming and snorkeling adventures. Just off the coast of St. Croix in the U.S. Virgin Islands, both beginner and novice snorkelers can dive up to 12 feet below the island’s surface in some of the prettiest waters in the world and explore the elkhorn-coral barrier reef, one of the most pristine in the Caribbean.

West Coasters know and love Catalina Island. Visitors to the island, which sit 22 miles southwest of Los Angeles, can embark on an ocean expedition, give fishing a try or go scuba diving with aquatic creatures.

Exploring the Champagne Reef might be one of the most dazzling and colorful adventures any swimmer or snorkeler can embark on. Named after its resemblance to Champagne due to the bubbling waters caused by active volcanoes that rise from the ocean floor, Champagne Reef is decorated with sponges with names like pink azure, red rope and purple vase. And when those aren’t enough to charm swimmers, undersea creatures — ranging from octopus, parrotfish, hawksbill turtles and seahorses — are sure to dazzle.

Cocos Island National Park is one of the most beautiful places in America’s national park system. A National World Heritage Site, Cocos Island has been named one of the best places in the world for diving.

Once a place of refuge for pirates, Nicaragua’s Corn Islands is now a dream Caribbean destination. Because of its stunning turquoise waters, reefs and eclectic marine life, the Corn Islands are a hotspot for snorkeling, scuba diving, kayaking and fishing.

Devil’s Bay Beach, located on the southwestern tip of Virgin Gorda — the third-largest of the British Virgin Islands — is a peaceful, private destination perfect for adventures like swimming and snorkeling in its crystal-clear waters.

Dry Tortugas is one of the most underrated national parks in America. Comprised of seven small islands, the park is known for its picturesque clear waters, ocean life, underwater shipwrecks and some of the most vibrant coral reefs in the Florida Keys. Less than 1% of the national park is dry land, meaning the best way to explore Dry Tortugas is by swimming, diving or snorkeling.

Located in Palawan, Philippines' largest province, El Nido is a gorgeous destination with black marble caves, corals, white sand and eclectic marine life. El Nido was dubbed “the most beautiful island in the world” by Travel + Leisure and has sights and sounds that will entrance any deep-sea explorer.

Named a Natural Protected Area and declared a World Heritage Site by UNESCO in 1995, Espiritu Santo Island is famous for having the largest sea lion colony in the world. Snorkelers and divers can interact with the sea lions in their natural habitat or spend time viewing tropical fish, like barracuda and parrotfish.

Hanauma Bay — located in America’s happiest state on the Hawaiian island of Oahu — is a protected marine life conservation area and underwater park. Hanauma Bay is a snorkeler’s paradise thanks to the hundreds of tropical fish and marine life that dot the waters. The beautiful bay, formed by a volcanic cone, was voted the best beach in the United States.

Kashiwajima Island is home to more than 1,000 different species of fish, making it a prime location for scuba diving in Japan. The island is known for its endless view of vibrant blue water and beautiful sunrises and sunsets across the horizon.

One of the best places to vacation for fans of swimming and snorkeling is Key West, Florida. Activities on the island range from boating and kayaking to getting up close and personal with dolphins.

Even locals love swimming and snorkeling at Knip Beach, a popular tourist destination. Visitors can swim in the warm waters or dive deep to explore the island’s reef. Kleine Knip Beach is also recognized for being an intimate destination. It’s one of the most romantic spots in the Caribbean.

The Maldives are one of the most mesmerizing places on earth. The nation of islands is comprised of 99% crystal clear waters and just 1% land, meaning water adventures are practically limitless. Swimming with manta rays and diving among more than 1,000 species of fish are bucket-list musts at this watery paradise.

Mauritius, located in the Indian Ocean, is a water sports paradise. The island has over 200  miles of coastline encircled by a coral barrier, and each diving location has a view worth seeing. The east diving region, for example, is rich in plankton, and the north diving region has colorful corals and sea animals. To top it all off, the stunning sights at Mauritius — like the sunrise and sunset over the clear waters — make the island perfect for an amazing romantic adventure.

Three miles from Maui’s southwestern coast in Hawaii is Molokini, a Marine Life Conservation District and Bird Sanctuary and popular diving and snorkeling destination. The island is only accessible by boat tours, but once guests make their way to Molokini, they’ll be among over 250 species of tropical, rainbow beaches described as a “kaleidoscope of coral.”

Nosy Be pairs gorgeous beaches with some of the world’s best seafood for an experience that exemplifies relaxation. On the tiny island off the coast of Madagascar, tourists can participate in recreational activities like snorkeling and swimming in blue waters.

The waters are so clear in Palau, you’ll forget you’re underwater. Snorkeling is one of the most popular activities at this warm-weather destination, with sea adventures possible for both novice and beginner snorkelers. Jellyfish Lake, home to the golden jellyfish and the moon jellyfish, and Dolphins Pacific, the world’s largest Dolphin Research Facility, are only two of the island’s fun attractions. At Jellyfish Lake, snorkelers can swim among jellyfish, and at Dolphins Pacific, they can interact with playful dolphins under an instructor’s supervision.

Visitors to Palomino Island, a private destination in Puerto Rico, can snorkel and swim all without ever needing a passport. Spanning a total of 100 acres, Palomino Island is a tropical paradise with gorgeous, clear waters with hues of blue and emerald green.

Swimming in Pig Beach in Exuma should be on every American’s bucket list. A Bahamian archipelago, the Exumas are bordered by dreamlike waters. Pig Beach is one of its most famous — and delightful — destinations. Swimmers can partake in fun activities like snagging a selfie with the swimming piggies or petting a stingray before snorkeling in the beautiful waters.

Located in Thingvellir National Park in Iceland, Silfra — which translates to “silvery” — Fissure is the only place in the world where people can dive between two continents at once as they swim between tectonic plates. Snorkeling in Silfra Fissure has been compared to flying as explorers roam gorgeous rock formations formed millions of years ago. Silfra Fissure is one of the world’s most unique natural wonders.

South Plazas, located in the Galapagos Islands near the east coast of Santa Cruz, is a small island known for its breathtaking colors. Between the months of May and December, the Galapagos carpetweed turns a brilliant red that rivals even the best fall foliage in your state. The island’s most popular snorkeling site is Punta Carrion. Views include multiple species of flora and fauna and one of the largest sea lion colonies in the Galapagos Islands.

Located in Grand Cayman — the largest of the Cayman Islands — Stingray City is one of the most popular tourist destinations in the world. Visitors have a once-in-a-lifetime opportunity to explore bright, blue waters populated with friendly southern Atlantic stingrays. And while swimming or snorkeling the day away with the stingrays, guests can also feed and snap fun photos with the aquatic creatures.

The U.S. Virgin Islands is one of many tropical island destinations that don’t require a passport to visit, and Trunk Bay Beach is arguably one of the best beaches in the world. The beach is a snorkeler’s paradise with a 225-yard-long snorkeling trail. And when not traversing open waters, there’s the beach to relax on.

Uepi is a snorkeling paradise. A barrier reef island in the Solomon Islands, Uepi is covered in tropical rainforest and framed by a warm lagoon on one side and a deep marine abyss — best known as “The Slot” — on the other. And animal lovers who dive or swim at Uepi are in for a treat: the island’s waters are populated with diverse marine life ranging from coral and starfish to masses of colorful fish. 

Utila — one of Honduras’ Bay Islands — attracts thousands of travelers hoping to snorkel in the region that contains the largest barrier reef in the Western Hemisphere: the Mesoamerican Reef. Utila is a destination worthy of seeing once in a lifetime.

Vieques is a Caribbean Island on the eastern coast of Puerto Rico. Vieques is home to Mosquito Bay, the brightest bioluminescent bay in the world. In this wonder of the world, organisms called Pyrodinium bahamense come into contact with another organism and create a bright burst of blue light that can be seen across the waters. Visitors can snorkel and swim as this phenomenon takes place for a once-in-a-lifetime experience. 

Located off the coast of Queensland, Australia, Whitsunday Islands is made up of 74 tropical islands in the heart of the Great Barrier Reef. Whitsunday is known for being one of the best spots in the world for swimming and diving. Green turtles, manta rays, parrotfish and the island’s famous Humphead Maori Wrasse named Elvis all roam the blue waters. After swimming with shy clownfish islanders call Nemo after the famous film, divers will feel like they’re visiting a movie location.

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