Loaded with major ions — the essential minerals (Ca, Mg).
Buoyancy
Standard buoyancy
LowHigh
Soft water — natural, classic buoyancy.
BicarbonatesSodiumCalcium
Tateshina Onsen Gongen no Yu, in Tateshina (Nagano), circulates bicarbonate water with a pH of 8, at 41°C, between an indoor bath and an outdoor rotenburo bath, with a sauna as well.
Insider tip — Gongen no Yu honours the mountain deity of Tateshina-san, a dormant volcano rising to 2530 metres above this highland resort plateau beloved by Tokyo weekenders. The bicarbonate spring is particularly prized in summer when the plateau wildflowers are in bloom and the air is cool even in August heat.