Loaded with major ions — the essential minerals (Ca, Mg).
Buoyancy
High buoyancy
LowHigh
Mineralised water — eases movement and joints.
CO2BicarbonatesMagnésium
Fujioka Onsen—Wisteria Hill Spring—takes its name from the wisteria (fuji) whose cascading purple blossoms have made it one of Japan's most celebrated flowering plants, associated with aristocratic refinement, the eponymous Fujiwara clan, and the transient beauty that is central to the Japanese aesthetic consciousness. The bicarbonate and carbonated waters deliver an effervescent, skin-stimulating mineral soak in which natural CO2 adds lively tactile sensation to the gentle alkaline warmth—a spring as refreshing and seasonally vivid as the wisteria blossoms that give its setting name. Rising in Gunma Prefecture, Fujioka Onsen connects the flowering beauty of the wisteria hill's spring season to the restorative mineral waters that emerge from the volcanic geology of Japan's most thermally prolific inland prefecture.
Insider tip — Fujioka Onsen rises in the southern Gunma plains near the city of Fujioka, where bicarbonate-carbonated waters from deep Cretaceous sediments produce a naturally effervescent bath. The combination of gentle carbonation and bicarbonate alkalinity is prized for improving skin texture and blood circulation. Its accessible location near the Joshinetsu Expressway makes it a convenient stop for travelers crossing between the Kanto and Chubu regions.