What is the largest coral reef in the world?

The Great Barrier Reef in Australia is recognized as the largest coral reef system in the world. It stretches over 2,300 kilometers (approximately 1,400 miles) and comprises around 2,900 individual reefs and 900 islands. This vast ecosystem is home to an incredibly diverse range of marine life, making it not only significant in size but also in ecological importance.

The Great Barrier Reef is a UNESCO World Heritage site and is known for its extensive biodiversity, including various species of corals, fish, mollusks, and marine mammals. Its expansive area and the variety of habitats it encompasses contribute to its status as the largest coral reef system, providing essential services like coastal protection, tourism, and fisheries.

While the other options mentioned have their own significance—like the Belize Barrier Reef being the largest reef in the Northern Hemisphere and the Coral Triangle known for its rich biodiversity—none match the sheer size and scale of the Great Barrier Reef. Thus, this coral reef stands out as the most extensive and notable on the planet.