Bessho Onsen, Ueda, Nagano Prefecture
Oyu Public Bath
The most balanced first stop if you only have time for one Bessho public bath: modest admission, an outdoor bath, historic atmosphere and two springs. Daishi-yu is the more direct pick for fully source-flowing water.
Check before bathing
- Opening hours
- 06:30–21:30; last admission 21:00. Normally closed Wednesdays.
Spring & water temperature
- Spring-source temperature
- About 50.6°C for No. 4 and 38.0°C for the naturally emerging Oyu spring.
- Bathing temperature
- Not published.
- Spring source
- Bessho Onsen No. 4 spring and the Oyu spring.
- Spring classification
- Simple sulfur-spring system; a separate analysis for the mixed water is not published.
- pH
- No. 4 spring's 2014 analysis lists pH 8.7 at the emergence point and 8.92 in the laboratory. The Oyu spring and mixed bath pH are not published; the No. 4 figure does not represent the entire bath.
- Flow rate
- About 900 L/min for shared No. 4 spring and about 60 L/min for the naturally emerging Oyu spring; these are source-level figures, not the amount delivered to Oyu's pools.
- Water handling
- Current property-district information says Oyu uses both No. 4 spring and the naturally emerging Oyu spring. The bath is described as source-flowing with circulation filtration.
- Analysis date
- 4
Bathing indications
General Bessho Onsen bathing indications are retained from official information. No treatment effect is inferred from the spring blend or outdoor bath.
Current admission is ¥300 for adults, ¥100 for elementary-school children and free for younger children. Oyu is the only one of the three public baths with a confirmed outdoor bath.
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.
