When most people envision scuba diving and snorkeling, they tend to imagine tropical locales with sandy beaches, turquoise water and brightly-colored fish. Places like the Caribbean, South America, and the South Pacific come to mind. But these aren't the only destinations where you can plunge below the surface and discover a whole new underwater world.

There are plenty of other places where you can see local sea life and dive historic shipwrecks far from the most-popular (and crowded) hot spots. Some are hot, some are cold, some are near, some are far, some are popular tourist destinations, and others are completely off the radar. Here are a few options for unique dive experiences that you may have never considered.

Iceland

The American and Eurasian continental plates meet at Iceland's Thingvellir National Park, where they are forming a rift in the land as they slowly move apart.

At Silfra Lake, the rift runs underwater. The water, which comes from melting glaciers, takes thousands of years to filter down through volcanic ash into the lake and is unbelievably clear.

Though you won't see fish in the ice-cold water, you will be treated to the vertigo-inducing sight of the deep fissure far below. Snorkelers will view it from above, while divers can actually descend into crack and explore the very depths of the earth.

Sudan

A politically unstable semi-desert country in northern Africa isn't the first place that people think of for world-class diving, but that's part of the appeal of diving in Sudan. It's so far off the beaten path that you'll encounter few other divers, so you'll be able to explore its many intriguing dive sights with no crowds.

Encounter reef and hammerhead sharks, manta rays, moray eels, and sea turtles at the Sha'ab Rumi reef, explore Jacques Cousteau's old stomping grounds at the Precontinent II, or explore the wreck of the Blue Belt cargo ship.

The ship sank in 1977 after being stuck on a reef. It's upside-down position and the presence of all its sunken cargo now makes it an exciting challenge for experienced divers.

Alaska

Alaska's Inside Passage offers over 15,000 miles of coastline around 1000 islands for divers to explore.

Waves are gentle in the area, and water temperatures can reach 65 degrees in the summer, allowing for nearly year-round diving.

Divers encounter plentiful crustaceans like sea urchins, sea stars, and kelp crabs and may spot orcas swimming in the distance.

Even seals and sea lions have been known to approach to investigate divers nearby.

Scotland

The ruggedly beautiful Orkney Islands are home to the shallow Scapa Flow harbor. Fifty-one German ships were sunk here at the end of World War I (with no loss of human life) and now the wrecks are popular diving spots.

Most of the wrecks are 110-160 feet down where divers can float in and around them and explore their various nooks and crannies. Drivers are free to enter the sunken ships, but cannot remove artifacts from under the sea.

Visibility varies from 6-60 feet so the ships cannot be seen in their entirety, but for most divers the chance to explore these antique warships up close is an unforgettable experience that makes up for the lack of crystal-clear water.

Egypt

Like Sudan, Egypt is another North African spot that offers surprisingly good diving. From Sharm El Sheikh, divers can descend into the warn waters of the Red Sea and explore sunken ships and underwater caves or dive among some of the most beautiful coral reefs in the world.

Among the bright, colorful coral and further out in the sea, you might also encounter sea turtles, manta rays, tuna and barracuda.

The Red Sea is also home to several varieties of sharks, including reef sharks, hammerhead sharks, nurse sharks and leopard sharks, making it a great destination for those looking to get up close to these marine predators.

America's Great Lakes

Scuba diving is most often synonymous with oceans, but there's also great diving to be found in many lakes around the world. For residents of Midwest states like Michigan and Wisconsin, these spots may be closer than they realize.

Rough waters and storms have taken down hundreds of boats in the waters of the Great Lakes in the last few centuries. The 185-foot steamer Vernon, the 280-foor steamer Lakeland and the 124-foot, three-masted schooner Rouse Simmons are among a few of the wrecks settled at the bottom on Lake Michigan.

Sardinia, Italy

The underground topography of the Italian island of Sardinia is just as diverse as the land above. From a sandy seabed covered in seaweed to reefs surrounded by brightly colored fish, you'll see a wide variety of underwater life diving in the waters of the Mediterranean Sea.

There's ample opportunity for wreck diving too, with over 100 boats lying beneath the surface around the island. One of the most beautiful features of the sea around Sardinia is the abundance of underwater caves and unique coral formations that divers can swim over, under and through.

Whether you are an avid diver or just beginning your certification process, you'll find exceptional dive spots all over the world. Escape the crowds and check out indigenous sea life and unique underground scenery by getting off the beaten dive path and visiting some less obvious spots for underwater exploration.

Photo credits: Iceland by r.gielen on Flickr, Sudan by welshcathy on Flickr, Alaska by DiveKarma on Flickr, Scotland by bill larnach on Flickr, Egypt by Tom Weilenmann on Flickr, Midwest by Fellowship of the Rich on Flickr, Sardinia by danielguip on Flickr

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