One of the most renowned marine ecosystems in the world, the Great Barrier Reef contains over 900 coral islands. The Heron coral island alone features over 20 diving sites that differ in the depth of the sea there. Reefs can be found as low as 5 metres below the surface of the water off the island. Agincourt Reef has marvellous coral canyons, and travellers can spot many turtles, crabs and starfish while enjoying the water sports. The wreck of SS Yongala can be explored by going for an underwater dip off Townsville, where diving can be done from Mackay to see the shipwreck of Llewellyn.
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