Loaded with major ions — the essential minerals (Ca, Mg).
Buoyancy
Standard buoyancy
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Soft water — natural, classic buoyancy.
BicarbonatesSodiumCalcium
Hotta Onsen in Takeo city, Saga prefecture, is part of the Takeo Onsen complex — one of Kyushu's most historic thermal sites, where bicarbonate-rich spring waters flow beneath a celebrated 1915 architectural gateway designed in the traditional Chinese-influenced style, now a nationally designated Important Cultural Property that has welcomed bathers for over 1,300 years. The Takeo onsen tradition was patronized by Toyotomi Hideyoshi's generals during the Korean campaign of the 1590s, making it one of the few Japanese spas with documented warrior therapeutic heritage from the Sengoku period. The surrounding Hizen region — gateway to the Imari and Arita porcelain producing areas whose blue-and-white ceramics once dominated European luxury markets — gives Takeo's onsen a rich context of Japanese artistic heritage alongside its therapeutic history.
Insider tip — Hotta Onsen lies within Takeo City in Saga Prefecture, a city whose bathhouses have served travelers on the Nagasaki Kaido road since the early Edo period. The bicarbonate waters are renowned for cosmetic properties and are marketed locally as bijin-no-yu, the bath of beautiful skin. Takeo Onsen's main public bath gateway, a flamboyant 1929 Art Nouveau arch, appears on regional tourism posters and is worth seeing as much as the water itself.