Kusatsuonsen Bouun
望雲
Gunma Kusatsu
群馬県 草津町
Kusatsuonsen Bouun
望雲
Gunma Kusatsu
群馬県 草津町
Onsen RyokanFree-Flowing Onsen
AT A GLANCE
Kusatsuonsen Bouun is an acidic spring, chloride spring, and sulfate spring (pH 1.8, strongly acidic). Naturally flowing (no recycling or dilution). Contains ≥50 mg/kg of metasilicic acid, certified as a beauty spring. Per Japan's Ministry of the Environment guidelines, indicated for atopic dermatitis and psoriasis.
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PRKusatsuonsen Bouun
From¥17,600/ person / night (tax incl.)
4.7(1302)
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USAGE
Free-Flowing Onsen
Pure spring water — no dilution, no recirculation
HeatedNo
DilutedNo
RecycledNo
FilteredNo
DisinfectedNo
AdditivesNo
▸Note
The temperature, pH and component values shown here are based on the hot spring analysis (source). Actual values in the bath may differ depending on heating, dilution, recycling and filtration. Please check current usage status at the facility.
REVIEWS
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✨ The descriptions, catch phrases, and translations on this page are generated by AI (Claude). pH, temperature, and component values are OCR-extracted from the official analysis report. Learn more