Australia's Great Barrier Reef is considered to be the world's largest reef system. It is made up of over 2,900 individual reefs, 900 islands and covers an area of 133,000 square miles (344,400 sq km). It is also one of the Seven Natural Wonders of the World, a UNESCO World Heritage Site and it is the world's biggest structure made out of living species. The Great Barrier Reef is also unique in that it is the only living organism that can be seen from space. The Great Barrier Reef is located in the Coral Sea. It is off the northeast coast of Australia's state of Queensland. The reef itself stretches over 1,600 miles (2,600 km) and most of it is between 9 and 93 miles (15 and 150 km) from shore. In places the reef is up to 40 miles (65 km) wide. The reef also includes Murray Island. Geographically, the Great Barrier Reef stretches from Torres Strait in the north to the area between Lady Elliot and Fraser Islands in the south. Much of the G...