The Great Barrier Reef is one of the Seven Natural Wonders of the World. It is the world's largest coral reef system. The reef is made up of millions and millions of a tiny organism called coral. It is a place where millions of plants and animals live. Native people in Australia have known about the Reef for thousands of years. It is important in their faith and culture. Learn more about The Great Barrier Reef in this well-constructed overview by Wonderville.