One unique and outstanding feature of Australia is the Great Barrier Reef. Extending 2,200 kilometers along the Queensland coast in the Coral Sea, it’s the largest reef system in the world, and the largest living structure on the planet. The incredible variety of life on the reef, over 10,000 species including 400 coral and 2,000 fish species, is unsurpassed anywhere in the world. It is a must see for everyone who visits the country.