Rich in active gases or metals — a strong mineral character.
Buoyancy
Standard buoyancy
LowHigh
Soft water — natural, classic buoyancy.
FerBicarbonatesManganèse
Kaju Takasu Futakoe Onsen, in Katsuyama, Fukui Prefecture, draws iron-rich water at 40°C. The facility has an indoor bath, a rotenburo and a sauna.
Insider tip — Kaju Takasu Futakoe Onsen taps iron-rich springs on the edge of the Okuetsu highlands in Fukui, producing waters with a subtle mineral tang and gentle rust hue. The baths are favored by locals for post-farming relaxation and are quieter than resort onsen. Soak in the indoor tub and then cool down on the wooden terrace overlooking forested hills.