Zao Onsen, Yamagata
Kamiyu Public Bath
One of Zao's simple, unmanned public bathhouses, with a relatively roomy indoor tub. It is a low-cost stop near the upper part of town, but there are no showers, taps or lockers, and soap is not allowed.
Check before bathing
- Opening hours
- 06:00–22:00 year-round. Adult ¥300; child ¥100. Payment is collected in an unmanned box. No dedicated parking.
Spring & water temperature
- Spring-source temperature
- 54.0°C.
- Bathing temperature
- Not published. The 43.0°C figure in public materials is a supply-point temperature, not a fixed bath reading.
- Spring source
- Oyu No. 1 spring.
- Spring classification
- Acidic sulfur-bearing aluminum sulfate-chloride spring; low-tonicity and high-temperature.
- pH
- Not published for this bathhouse; do not substitute the Zao area figure.
- Flow rate
- Not published for this bathhouse.
- Water handling
- The published spring notice says well water is added to adjust temperature; no heating, circulation or disinfectant is used, and the bath is full-discharge source-flowing. There are no showers or taps, and soap is not allowed.
Bathing indications
The area authority publishes general bathing indications for Zao Onsen; this is not a promise of medical benefit.
No showers, taps or lockable lockers; soap is prohibited.
How to read a bath profile
Spring-source temperature and actual bathing temperature are kept separate. Each score is shown independently for comparison rather than collapsed into one overall score.
