Were it not for the well-nourished faces of the passengers suffused with keen expressions of expectation and purpose, the supine bodies, unpacked food, luggage and blankets strewn across the hard flooring of the ferry's modern equivalent of steerage class resembled those of a migrant ship.

Almost three hours later, we arrived no worse for wear at Beppu, the local port on Nishinoshima, one of four inhabited landfalls in the Oki Islands of Shimane Prefecture. Unlike Japan's southern littorals, where the first features of interest are their white, coral peripheries, Nishinoshima is noted for the greenery of its shorelines, rising like forests out of the sea.

A caldera formed from the eroded summits of stratovolcanoes of immense proportions and a thermal power that can only be imagined. The cliffs of Oki erupted from the salt waters, scalding hot, then froze in abrupt verticality, like the edges of giant massifs. They are fine examples of the drama that geology can sometimes offer us. The eruption may have been the most exciting event visited upon the islands for millennia. It is not excitement, though, but the prospect of experiencing these pristine, rural-marine environs that draws a small but discerning number of visitors to the islands.