Seven wonders of the natural world – in pictures
The Aussies are justifiably proud of the largest coral reef on earth – the Great Barrier Reef. It can be seen from space and is believed to be the world’s biggest single structure made from living organisms. Composed of some 3,000 individual reefs and 900 islands, it stretches for 1,616 miles and is strung out over 133,000 square miles of the Coral Sea in Queensland, north east Australia.