The world's largest coral reef is the Great Barrier Reef, located off the coast of Queensland, Australia. Spanning over 2,300 kilometers (approximately 1,430 miles), it is composed of over 2,900 individual reefs and 900 islands, making it a UNESCO World Heritage Site. The Great Barrier Reef is renowned for its biodiversity, housing thousands of species, including corals, fish, mollusks, and marine mammals. It's considered one of the most complex ecosystems on the planet and is a crucial area for marine research and conservation efforts. Tourists from around the world visit to experience its stunning beauty and vibrant marine life.