Australia's Great Barrier Reef: The wonder down under

On June 27, 2000 history was made when the Olympic flame went underwater at the Great Barrier Reef. A lamp was specifically designed for this leg of the relay and marine biologist Wendy Craig Duncan swam with the torch among the coral and fish of Agincourt Reef.

Almost everyone has heard of Australia's Great Barrier Reef, and almost every scuba diver has dreamed of diving there.

The Great Barrier Reef Marine Park Authority protects the famous reef. It's an amazing 1,250 miles (2000-km) or more long, stretching from Papua new Guinea in the north to Lady Elliot Island off Bundaberg in Queensland to the south. Considered one of the world's natural wonders, it is the most extensive reef system and the biggest structure made by living organisms on earth. It consists of approximately 2,000 individual reefs and 71 coral islands, scattered like jewels in the ocean.

The Great Barrier Reef is home to a remarkable number of sea creatures. The coral itself is made up of the skeletons of tiny, flowerlike water animals called polyps, held together by a limestone substance produced by a type of algae. Hundreds of polyp species form the coral in a dazzling display of colors and shapes. The reef also supports as many as 2000 species of fish.

Some popular dive spots include:

Cod Hole - A sheltered reef line east-northeast of Lizard Island. The reef sustains enormous cod groupers, Napoleon wrasse, moray eels, and other reef dwellers. Some dive boats visit the site, but this is essentially a live-aboard site.

Yongala Wreck - This wreck lies about 200 miles (322-km) south of Cod Hole. It supports a dense growth of coral and groups of fish. Here you'll encounter soft corals, schooling snappers, eagle rays, jacks, cobia, Napoleon wrasse, flowery cod, and barramundi cod. Other sites include stingrays, groupers, sharks, turtles and sea snakes. Although rich with marine life, visibility is poor and currents are strong.

Pixie Pinnacle - South of Cod Hole, it's a 90 foot (27-m) tall pinnacle of coral sitting in a tidal flow. This is a live-aboard only site. You'll find nudibranches, clownfish, fairy basslets, rabbitfish, stonefish, and lionfish here. Beyond the outer edge of the Great Barrier Reef lies the Coral Sea. It was the scene of a U.S. victory (1942) that checked the southward expansion of the Japanese forces in World War II.

Source: scuba.about.com