Also known as Retoka, Eratoka and Eradaka Island, with assorted spellings according to your native language. Since Vanuatu has 127 languages and was colonised by the British and French, most of the place names are remarkably schizophrenic.

Hat Island is, of course, shaped like a hat, a large sombrero in fact, this because it is an old volcanic plug. Essentially it's the heart of an ancient submarine volcano where the outside has eroded away and the inside core of basalt has been covered in coral. Despite global warming, because of plate tectonics, Vanuatu is emerging out of the sea. The landscape beneath the water reflects that above. Old lava tunnels and dykes covered in coral, and sheer underwater walls.

No one lives on the island full time. It's supposedly deserted, and was, until recently, also called the island of the dead, or the ghost island (see Roymata's grave). In fact the local Natapao villagers from nearby Lelepa Island are known to spend a few days here, fishing and collecting turtle eggs. (They are careful never to take more than a few eggs from each nest). The island's wildlife consists of goats, and a few more goats, placed there for possible shipwrecked travellers - a common practice a few hundred years ago.

The climb to the top of the island, where there's an automatic lighthouse, is not really worth the trouble, although the views of the surrounding reef from this perspective are excellent.