Great Barrier Reef off Heron Island
Stetching more than 2,300km along the northeast coast of Australia, lies the world's largest reef and the only living structure visible from the moon. The Great Barrier Reef, made up of about 2,900 unconnected coral reefs and roughly 900 islands, is home to over 1,500 species of fish and 400 species of coral making it one of the most important marine ecoystems on Earth. Each year more than 1.8 million tourists visit the reef, spending an estimated 4.3 billion Australian dollars on reef-related industries from diving to boat rental to posh island resort stays. Revenue from tourism -- popular activities include snorkelling; scuba diving; fishing; glass-bottomed boat and semi-submersible vessel excursions -- dwarfs the commercial and recreational fishing industries which generate 360 Australian dollars annually.
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