Great Barrier Reef, Queensland, Australia

Great Barrier Reef, Queensland, Australia

At 344,401 square kilometres, the Great Barrier Reef is about half the size of Texas, a stat that becomes even more amazing when you learn the reef was created by teeny, tiny marine invertebrates. Coral reefs are formed when colonies of coral polyps secrete hard exoskeletons made of calcium carbonate, slowly building an underwater home to support marine life of all shapes and sizes. That’s a feat worth protecting.