The largest living structure on the globe, the Great Barrier Reef is comprised of over 2,900 individual reefs and 900 islands; it stretches more than 1,400 miles long the Coral Sea off the coast of Queensland, Australia. Within its 133,000 square miles, the array of life is almost hard to fathom. Amongst the tangle of colorful reefs, more than 600 types of coral reside along with more than 100 species of jellyfish, 1,625 types of fish, 133 varieties of sharks and rays, and more than 30 species of whales and dolphins. That’s a lot of sea creatures! It is one of the most complex ecosystems around; it’s diversity is only matched by its physical beauty. Plus: heart-shaped reefs (swoon!).