The Great Barrier Reef is the largest coral reef on the planet and for that reason alone, it's on most people's diving wish list. There are 3000 individual reefs, 1500 species of fish, 400 corals and 4000 molluscs. Although you can dive all the way along this impressive natural structure, the Ribbon Reefs are perhaps the most popular and most dived. They wind down the Queensland coast, defining the outer edge of the continental shelf before it drops off into the deep water, Queensland trench.
The Ribbon Reefs are characterised by two styles of dive – gently sloping rim reefs and more dramatic pinnacle dives. These tend to be tall, thin rocks, like an inverted chimney, that soar from around 30 metres until they almost break the surface. There's usually a mass of snappers, large schools of jacks, tuna and mackerel swimming around them. Smaller creatures include shrimp in mushroom corals or anemones, whip coral gobies, nudibranchs, leaffish and the usual tropical fish.
The world-famous Cod Hole dive site is at the top of this area, and you are almost guaranteed to see these enormous and curious animals. In the winter months (June and July) dwarf minke whales are frequent visitors to the Great Barrier Reef. You can snorkel with them and – if you are really lucky – they may visit during a dive.