Rich in active gases or metals — a strong mineral character.
Buoyancy
Standard buoyancy
LowHigh
Soft water — natural, classic buoyancy.
SoufreSulfuresSulfates
Myoko Onsen Sekikawa Kyodo Yokujo Oyu, in Myōkō, Niigata, taps sulfurous water at 44°C. An indoor bath, an outdoor rotenburo and a sauna are available.
Insider tip — Sekikawa Oyu serves the Myōkō Onsen village in the volcanic Niigata highlands where the communal outdoor bath (kyodo yokujo) tradition of shared public bathing preserves the original social fabric of Japanese thermal culture. Myōkō ski resort above the spring is one of Japan premier powder snow destinations — the Myōkō volcanic massif traps Sea of Japan moisture to deliver over 11 metres of annual snowfall — and the sulfurous springs emerging from the Sekikawa geothermal zone have warmed skiers and pilgrims in this remote Niigata mountain community for over three centuries.