Some natural phenomenon and places are too important to the human race. Whenever you find a place on this planet earth which is naturally unique in one sense of the word or the other, you always want to see it. This is the case with the Great Barrier Reef. It is the most unique and interesting place to visit. As it is a very important place, there are a lot of people from all parts of the world who come to visit this place every year. There are many special features which are attached to this barrier reef. The reef is the work of the corals and the other coelenterates living in the sea. The Great Barrier Reef has been built by the calcium deposits of these animals over a period of thousands and thousands of years. It is now the greatest and largest features of the earth which is natural. There are many artificial or man made features on this planet earth which are larger than the Great Barrier reef, but there is no other natural feature which is as large as this reef.