Third biggest island of the Marquesas, Ua Pu is located 35 km to the south of Nuku Hiva. It is famous for its four high basalt pillars raising to the sky as the towers of a fortified castle. One of them is Mount Oave, which reaches to 1230 metres in the middle of the island, constituting the highest summit of the Marquesas archipelago.
The pillars of Ua Pu formed during volcanic eruptions thanks to a very viscous lava.