Palau

Ranked as Number OneIt is 500 miles (800km) east of the Philippines and 2000 miles (3200km) south of Tokyo. Manta rays and eagle rays are attracted to these plankton-fill waters.

The Belize Barrier Reef

This is the second largest coral reef system in the world after the Great Barrier Reef in Australia. Nassau grouper makes it home here. It is remarkable for its ability to change sex as it gets older, increasing its chances for reproductive success when another grouper is met.

The Galapagos Islands

The name is derived from the Spanish name given to the Giant Land Tortoises that inhabit these islands.

The Northern Red Sea

This is "George", a humphead wrasse. He is the "welcome" fish that is always on a look out for hand outs from the divers.

Lake Baikal

This "Sacred Lake" is 25 million years old and it is also the deepest lake, holding more water than all of North America's Great Lakes combined. It is also home to the world's only fresh water seal - the Baikal seal, or nerpa.

The Great Barrier Reef

Spanning more than 2000 km along the northeastern coast of Australia, the Great Barrier Reef is home to thousands of species of plants and animals.

The Deep Sea Vents

The most fascinating of the world's underwater creatures can be found here. No sunlight ever penetrates its deep waters. Marine biologists can study the food chain that functions without sunlight, which they had once thought was not possible.