The Great Barrier Reef and the Coral Sea The Great Barrier Reef is the world largest reef system and it has about twenty nine hundred individual reefs, the reef is located in the Coral Sea. The coral reef is built up of many millions of small tiny organisms called coral polyps. According to the Australians the Great Barrier Reef is the eight wonder of the world. Then again, a lot of people feel that this is an understatement. The Great Barrier Reef is the only living organism on plant earth that can be seen even from space. The