Snorkelers and divers can explore between two continents at Iceland's Silfra rift. — Photo courtesy of Diego Delso
Snorkel the fissure between Europe and North America
Tectonic plates drift about ¾ of an inch each year, widening the continental gap at Iceland’s Thingvellir National Park, a World Heritage Site. Plunge into its cold, piercingly clear sapphire water with The Sport Diving School of Iceland, then look for trout among the rust-red rocks and neon-green “troll hair” algae.
Float over Roman ruins
Volcanic activity collapsed the coastline in the 16th century, flooding the columns, statues and elaborate mosaics of an ancient resort near Naples, Italy. Now outfitters like Centro Sub Campi Flegrei lead tours of the Underwater Archaeological Park of Baia.
Five new subspecies of Mastigias papua jellyfish live in the Rock Islands Southern Lagoon, a World Heritage site. — Photo courtesy of Amanda Castleman
Snuggle endangered, non-stinging jellyfish in Palau
Isolated in a marine lake, golden jellies have lost the ability to sting (much)… This allows snorkelers to paddle carefully among their pulsing tendrils with outfitters like Sam’s Tours.
Spy on salmon in British Columbia, Canada
Strap on a mask and shoot downstream from Bear Claw Lodge, zooming over huge-eyed salmon fingerlings. Then watch fish battle upstream at Campbell River or courting in Shuswap Lake, where sockeyes–with moss-green heads and cherry-red bodies–pair off before spawning.
Snorkel Alaska reveals the vibrant color under the waves in Ketchikan. — Photo courtesy of Amanda Castleman
Swim above Southeast Alaskan tidepools
The Land of the Midnight Sun has a chilly reputation, but Ketchikan’s shallows can reach 65 degrees Fahrenheit. Squeeze into a thick 7mm wetsuit and check out the vibrant colors below the grey waves–like golden kelp, purple urchins and orange blood stars–with Snorkel Alaska.
Snorkel sparkling seas in Puerto Rico
Nightly, bioluminescence creates constellations in the bay of La Parguera. Float among glowing plankton with Paradise Scuba and Snorkel Center, then finish the evening with beer and homemade empanadillas.
Flow Bonaire takes snorkelers into some of the island's 400 caves. — Photo courtesy of Abi Smigel Mullens
Explore submerged caves in Bonaire
Clamber down ladders into one of the Caribbean island’s 400 grottos, then slip into the clear, turquoise water. Visitors can freedive among the stalactites and stalagmites, when accompanied by guides from a licensed company like Flow Bonaire.
Summer with belugas off Churchill, Canada
Curious white whales often cavort alongside snorkelers clad in thick Arctic wetsuits. Listen to their vocalizations and echolocation clicks, as their exhaled breath bubbles around you, on expeditions with companies such as Sea North Tours.
Competitors must dog paddle at the World Bog Snorkelling Championship (no crawl or breaststroke). — Photo courtesy of Fotograferen.net
Battle through the mire in Wales
In late August, Llanwrtyd Wells hosts the World Bog Snorkelling Championships. Around 130 international competitors belly down into a muddy 180-foot trench, darkened by peat, and try for the fastest sprint.
Cooling down in Mexican cenotes
Once considered sacred entrances to the underworld, the Riviera Maya’s sinkholes contain stalactites and stalagmites, as well as fossils of sloths, mammoths and giant jaguars. Snorkelers can paddle around the water-lily-fringed entry to the world’s second-longest submerged cave system with Dive Cenotes Mexico.