| Heron is a tiny Barrier Reef coral cay, of only 17 hectares, in the Capricornia Group of islands of Australia's Great Barrier Reef. |
| We anchor alone in the lee of the cay, pile into the inflatable dinghy, don our masks and fins, and spend the next hour swimming with dolphins. |
| If you're a non-swimmer, take a tour that brings you to a coral cay rather than the open sea. |
| The Pandora survivors managed to climb aboard tenders and reach the safety of a sand cay. |
| How policy trickles down from UNESCO headquarters in Europe to a sand cay on the outer edge of the Great Barrier Reef half a world away is something else entirely. |
| Flat as a washed-up jellyfish, the 217 hectare sand cay is only 4m above sea level at its highest point. |
