Western Rocky

The dive starts at about 12 m below the surface on a large plateau, with finger-shaped reefs stretching out from it into deeper water to a maximum of close to 40 m. Currents permitting, it is possible to swim all the way around the island in one dive; when they are running you can find shelter on the plateau and still have plenty of reef to last a tank. Anemones and pore corals cover the rock, with thousands of glassfish over them being hunted by trevally.

On the southern wall a large cavern starts 5 m below the surface and drops to 25 m. East of the cavern is the entrance to the tunnel that runs right through the centre of the island and exits on the northern side. It runs from 17 m down to a maximum of 24 m, with daylight just visible for the whole 30 metres of it. Everything inside is big: gigantic lobster, and nurse sharks so fat that one about three metres long can make it impossible to get through.

As the tunnel reaches the northern side it gradually narrows until divers must progress in single file, then splits into two exit passages that open onto a fringing reef at 21 m. The left passage may require you to remove your scuba unit to squeeze through. Outside, fimbriated moray eels are common and banded sea snakes can be seen, while whitetip reef sharks hold around small rocks a short swim from the wall in deeper water. Marine life here runs from the tiniest nudibranch to occasional whale shark visits.