Oshima Island

Oshima is the southernmost of the three islands east of Fukue in the Goto archipelago, home to one of the largest lava tubes in the island chain. The 130-meter tube runs into the unpopulated southern side of the island, its walls covered in shining pyrite crystals and the ceiling hung with volcanic stalactites. Researchers from nearby universities are currently studying cave animals they believe may be unique to Oshima. The island also has Mt. Hosogatake on its western edge, officially Nagasaki Prefecture's lowest mountain at just 25 meters. The village of around 50 residents has a post office and a Buddhist temple with a statue-lined garden. Accommodation is available.