Osaka Ibaraki City
A full-scale bathing facility with heat-wave löyly, an ice-cold cold plunge bath, and free-flowing source hot spring water
Saito Natural Hot Spring Sumire no Yu is a super sento in Ibaraki, Osaka. Its authentic sauna, featuring heat-wave service by a sauna master and frequent automatic löyly, pairs with a cold plunge bath lined with binchotan charcoal to deliver an intense hot-and-cold alternating bath experience. The light brown simple hot spring that gushes from 1000 m underground also has a free-flowing source bath, and its soft texture keeps you warm and cozy long after you get out.
A mildly alkaline simple hot spring that springs from 1000 meters underground. The light brown water is its hallmark, and the source bath lets you enjoy fresh water flowing continuously. With its soft texture, it warms the body from deep within.
A full-scale sauna kept at a consistently high humidity by automatic löyly that runs frequently. Heat-wave service by a sauna master is also offered, allowing you to sweat profusely at once in pleasantly intense heat that seems to pierce the body.
A low-temperature steam bath filled with the soothing aroma of kampo herbal medicine. Gentle steam wraps the body softly, providing a relaxing sweating experience without any breathlessness while moisturizing the skin.
A cold plunge bath lined with binchotan charcoal. Its defining feature is an intense, stabbing coldness that instantly cools down a body heated to the limit in the sauna, delivering the ultimate toning effect.
Irregular Holidays
Visited by the Editor-in-Chief
The Editor-in-Chief visited in person in May 2026
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