Rich in active gases or metals — a strong mineral character.
Buoyancy
Standard buoyancy
LowHigh
Soft water — natural, classic buoyancy.
SoufreSulfuresSulfates
Biratori Onsen Yukara, in the Hidaka district of Hokkaido, heats sulfurous, iron-rich water to 44°C (pH 6.5). The facility offers an indoor bath, an outdoor rotenburo and a sauna.
Insider tip — Biratori Onsen Yukara lies in the Hidaka mountains of central Hokkaido, a region of active volcanism and indigenous Ainu heritage. The hot spring waters carry notable sulfurous and iron-rich mineral content characteristic of the volcanic terrain. The facility is named in honor of Ainu cultural traditions and offers a quiet, rural retreat far from urban crowds. Winter visits reveal snow-dusted forests surrounding the baths, while summer brings the verdant Hidaka valley in full bloom.