The island’s nickname came from its apparent resemblance to a battleship. The clue to the island’s mystery lies in coal mining. Reached by long descending tunnels, coal beds below the bottom of the ocean near Hashima disgorged huge quantities of high-grade coal for almost a century. But in 1974 the inhabitants abandoned the island to the wind and salt spray, leaving behind only unneeded belongings and a few stray cats that could not be captured. A closer look reveals clusters of unpopulated high-rise buildings pressing up against a man-made wall, a battered shrine at the top of a steep rock cliff, and not a single tree in sight.