Loaded with major ions — the essential minerals (Ca, Mg).
Buoyancy
Standard buoyancy
LowHigh
Soft water — natural, classic buoyancy.
CalciumSulfatesMagnésium
Hatsutani Onsen is a hot spring resort in Nagano Prefecture in the heart of the Japanese Alps, whose sulfated mineral waters have been appreciated by visitors drawn to the spectacular mountain scenery and highland cultural heritage of this thermally active region. Nagano Prefecture hosted the 1998 Winter Olympic Games at Nagano City and the nearby ski resorts, and its combination of world-class alpine winter sports, hot spring bathing, and traditional mountain culture makes it one of Japan's most appealing year-round destinations. The sulfated waters of Hatsutani Onsen are associated within Japanese bathing tradition with rest and muscular relaxation, making this spring particularly well suited to visitors who combine thermal bathing with hiking or skiing in the surrounding mountain environment.
Insider tip — Hatsutani Onsen is a mountain spring in the upper Agatsuma valley of Gunma, fed by calcium-sulfate waters that deposit faint white crusts on the wooden bath surrounds. The spring temperature is high enough to require a brief cool-down channel before the main pool, and the concentrated mineral content is prized locally for easing muscle stiffness after farm work. A single family-run inn has maintained the source for four generations, keeping the atmosphere authentically rural. The maple-lined gorge path leading to the bathhouse is at its most spectacular during the brief October foliage peak.
