Add Yahoo as a preferred source to see more of our stories on Google. The Great Barrier Reef is the world’s largest living structure, so big, it can be seen from space. Photograph by Kieran Stone, ...

This article was produced by National Geographic Traveller (UK). The first time a giant trevally fish hits me on the forehead, I freeze. We're 39ft below the surface of the ocean at dusk, the inky ...