Great Barrier Reef, Australia

Preview A small giant clam -- yes, that's it's real name -- in Australia's Great Barrier Reef.
(Chuck Savall)

The Great Barrier Reef site in Australia was inscribed on the World Heritage List in 1981. The site is the world’s most extensive stretch of coral reef with probably the richest animal diversity anywhere. There are over 1,500 species of fish, about 400 types of coral, 4,000 types of mollusk (including the small giant clam, Tridacna maxima, pictured here), and a diverse assemblage of sponges, anemones, marine worms, crustaceans, and many other invertebrate and vertebrate species. The “GBR” provides refuge, habitat, and resources for several endangered species, including dugong (Dugong dugon) and sea turtle feeding grounds and nesting grounds for green turtles (Chelonia mydas) and loggerhead turtles (Caretta caretta).

Today, over 40 World Heritage sites are listed for their marine values. Together, they can be considered the “Crown Jewels of our Ocean” and are recognized for their outstanding beauty, exceptional biodiversity, or unique ecological, biological, or geological processes. See more photos and learn about other Marine World Heritage sites.