Loaded with major ions — the essential minerals (Ca, Mg).
Buoyancy
Standard buoyancy
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Soft water — natural, classic buoyancy.
CalciumSulfatesMagnésium
Funayama Onsen is a sulfated hot spring in Japan, its waters rich in calcium and magnesium sulfates that give them a smooth, skin-conditioning character valued in traditional Japanese balneology for their benefits to circulation and joint flexibility. The name Funayama—evoking the image of a mountain shaped like a vessel or a ship—suggests a spring cradled within distinctive upland terrain where geology and landscape are inseparably linked. Sulfated springs like Funayama offer a pleasant, clear water appearance that contrasts with the more dramatically colored volcanic springs of Japan's famous resort destinations.
Insider tip — Funayama Onsen draws calcium-sulfate waters from the foothills northwest of Mount Fuji, where ancient volcanic geology infuses the aquifer with high mineral content. The chalky water deposits distinctive white precipitates in the baths and is prized locally for soothing arthritic joints. On clear days the upper baths frame a perfect silhouette of Fuji, making this one of the more picturesque onsen approaches within the World Heritage zone.
