The Great Barrier Reef is a beautiful place. The Great Barrier Reef Located in the Coral Sea, off the coast of Queensland in northeast Australia, the Great Barrier Reef is a World Heritage eco holiday destination, with a range of environmental tourism operators available providing educational and interpretive information on the reef. The Great Barrier Reef is the largest coral reef system composed of over 2,900 individual reefs and 900 islands stretching for over 3,000 kilometers (1,600 mi) over an area of approximately 344,400 square kilometers (133,000 sq mi). The reef is located in the Coral Sea, off the coast of Queensland in northeast Australia.The Great Barrier Reef is made up of many millions of tiny organisms, known as coral polyps. Corals belong to the group of animals (Cnidarians) that also include anemones, jellyfish, bluebottles and hydroids and the coral polyp is a small tube-like structure, with a central space opening via a mouth. Most corals also contain zooxanthellae (pronounced zo-zan-thel-y), a single-celled algae that live inside the coral animal and help to supply it with food.