What is the name of the largest coral reef system?

The largest coral reef system is the Great Barrier Reef. It lies in the Coral Sea off Queensland, Australia, and stretches for more than 2,300 kilometres along the coast.

The Great Barrier Reef is not one continuous wall of coral. It is a vast network containing more than 2,900 individual reefs and about 900 islands. Billions of tiny coral polyps build its limestone framework over many generations, creating habitats for fish, turtles, molluscs and other marine life.

The modern reef system developed after the last Ice Age, as rising sea levels submerged coastal hills and allowed corals to grow upward and outward. Much of the visible reef structure is estimated to be about 6,000 to 8,000 years old, although older reef-building phases existed in the region.

A common mix-up is confusing the Great Barrier Reef with the Great Barrier Reef World Heritage Area. The latter is a protected region that includes the reef system and surrounding marine environments. The reef is also often called the world's largest structure made by living organisms.