The Great Barrier Reef stretches 2,300km from the northeastern tip of Australia to Bundaberg (Queensland). Longer than the Chinese Wall, visible from the moon, and World Heritage since 1981, it is considered the 8th wonder of the world!

Characteristics of the Great Barrier Reef

The Great Barrier Reef is the largest coral reef in the world. It consists of more than 2,000 islands (some parts of which have never been explored) and nearly 3,000 reefs.

The closest reefs are 30km off the coast. To see beautiful coral beds and incredible fish, you have to go further.

The corals are relatively close to the surface because they need light to develop. Therefore, it is difficult to find them below 30m depth.

The reefs of the Great Barrier Reef can be classified into 3 categories:

Barrier: Formed by coral skeletons and a living upper layer.

Platform Reefs: External part, created by the growth of corals up to the surface of the water. This forms a sandbank and sometimes even vegetation settles there.
Fringing Reef (continental islands): Closer to the mainland, such as the Great Keppel Islands and most of the Whitsunday Islands. They were once attached to the mainland and got then separated by rising waters

great barrier reef 1

Some statistics:


  • Length: 2,300km
  • Average width: 65km
  • Maximum width: 80km
  • Distance from the coast: between 15 and 150km
  • Age: over 10,000 years
  • More than 400 kinds of corals
  • 1500 kinds of tropical fish
  • 20 types of reptiles, including sea turtles
  • 200 types of birds
  • Rays, sharks, tunas, dugongs, dolphins, and humpback whales that migrate from the Antarctic!


  • Jelly Fish: From October to May, less present around the islands.
  • Stone Fish: Fish that have deadly poisonous spines

Threats to the Great Barrier Reef

Even though it is increasing in size, the Great Barrier Reef is an extremely fragile ecosystem. It is moving slowly towards the south, which benefits from warmer waters due to global warming. It is threatened by boats and their anchors, intensive fishing, divers, marine pollution, and of course, global warming. Some scientists even estimate that by 2050 only 5% of live corals will remain. Fortunately, the Australian government is well aware of these environmental issues and has launched new measures to protect the Great Barrier Reef in 2004.

great barrier reef

Endangered species

The sea turtle (Green Sea Turtle) that has inhabited the oceans for 150 million years. Six of the seven species of sea turtles are present in the Great Barrier Reef and all six of them are threatened. The dugong is the only marine mammal that feeds exclusively on plants. There are 1,400 dugongs living at the Great Barrier Reef.

Humpback whales, visible in the region between May and September. They spend the summer in the polar regions where food is abundant, then come to the warm waters of Australia in winter to mate . They are protected and some species are threatened.

How to preserve coral

Here are a few tips to minimise your impact during your visit:

  • Visiting: Use toilets as much as possible, take your garbage, check your belongings for insects (or any other living species) before visiting.
  • Excursion: Don’t stand on corals, don’t touch them, try not to frighten any animals, don’t feed any fish, and take your time!
  • Camping: Take your garbage back to the mainland, obtain a permit from the Queensland Parks and Wildlife Service, camp only on the designated sites, don’t make fires in the national parks, don’t use detergent near the water, use sand to clean your dishes.

Departure locations for tours to the Great Barrier Reef

  • Cairns: The most popular
  • Port Douglas: Good access to Agincourt Ribbon Ree
  • Cape Tribulation: Less crowded
  • Airlie Beach: Departure for Whitsundays

The best season to go to the Great Barrier Reef

The Great Barrier Reef has a tropical climate with pleasant temperatures all year round. There are two main seasons: the hot and humid summer from December to April and the dry and cooler winter from June to November.

The rainy season lasts from December to March. However, the islands of the Great Barrier Reef are much less effected by storms than the continent. Nevertheless, jellyfish pose a danger. You should be fine with a wetsuit though! Another solution is choosing an island very far south or very far from shore (islands such as Brampton, Heron, and Lady Elliot island). These islands are never affected by jellyfish.

Water temperatures range from an average of 21°C in winter to 27°C in summer. The further you move north the hotter it gets.

The best time to go diving is between April and November.

Updated on the 24/10/2019. Initially published on the 29/08/2018.

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