The Great Barrier Reef is the world’s largest reef system composed of over 2,900 individual reefs and 900 islands stretching over an area of 344,000 square kilometres. The reef is located in the Coral Sea, off the coast of Queensland in north-east Australia. Approximately two million people visit the Great Barrier Reef each year.

The Great Barrier Reef is the world’s biggest single structure made by living organisms. This reef structure is composed of and built by billions of coral polyps. This reef supports a wide diversity of life, and was selected as a World Heritage Site in 1981. The National Trust Queensland named it a state icon of Queensland.

A large part of the reef is protected by the Great Barrier Reef Marine Park, which helps to limit the impact of human use, such as fishing and tourism. Other environmental pressures on the reef and its ecosystem include runoff, climate change accompanied by mass coral bleaching, and cyclic population outbreaks of the crown-of-thorns starfish. The crown-of-thorns starfish (see photo below)) preys on coral polyps. Large outbreaks of these starfish can devastate reefs. In 2000, an outbreak contributed to a loss of 66% of live coral cover on sampled reefs in a study by the RRC (Reefs Research Centre.) Outbreaks are believed to occur in natural cycles, worsened by poor water quality and overfishing of the starfish’s predators.

The Great Barrier Reef hosts 30 species of whales, dolphins, and porpoises, including the dwarf minke whale, Indo-Pacific humpback dolphin, and the humpback whale. Large populations of dugongs live there.

Read more about the Great Barrier Reef.

Photo of the Sea Turtle, Great Barrier Reef, Australia by Sam Harris.

When planing your visit consider taking some time to visit the Daintree Rainforest, which is the oldest rainforest in the world.