Goshogake Onsen Semboku

Goshogake Onsen, located high on the Hachimantai volcanic plateau straddling the Akita-Iwate border in Semboku, Akita, is one of northeastern Japan's most dramatically geothermal onsen — set within a landscape of steaming fumaroles, boiling mud pools, and sulphurous gas vents that make the surrounding hillside resemble a volcanic moonscape at nearly 1,000 metres altitude. The chloride and bicarbonate thermal waters are dispensed through multiple bathing facilities including the famously therapeutic mud bath (doroburo), where guests immerse in naturally warm volcanic mud for skin and joint treatments that have no equivalent among Japan's more conventional onsen. The remote mountain location, surrounded by the beech-forest wilderness of the Hachimantai National Park — a highland plateau famous for its marshes, alpine flowers, and winter skiing — gives Goshogake an elemental wildness that draws onsen enthusiasts seeking Japan's most primordially volcanic bathing experiences.