By Lake Suwa, Shimosuwa Onsen, Shimosuwa, Nagano Prefecture
Kohan-no-Yu
A good-value stop after a walk by Lake Suwa or a drive through the area, with a large indoor bath and an open-air pool. For the historic post-town and Akimiya, the northern baths are better placed.
Check before bathing
- Opening hours
- 07:00–21:30. Check for special-event changes before visiting; the facility closed on 15 August 2026 for the fireworks festival.
- Access
- Parking is available.
- Tattoo policy
- The facility's current first-party information does not confirm a tattoo policy. Check with the bathhouse before visiting.
Spring & water temperature
- Spring-source temperature
- Not published.
- Bathing temperature
- Not published.
- Spring source
- Shimosuwa Onsen; the individual spring source is not published.
- Spring classification
- Natural hot spring; the current tourism pages do not publish a facility-specific chemical classification.
- pH
- Not published.
- Flow rate
- Not published.
- Water handling
- The official listing identifies Kohan-no-Yu as a public bath in Shimosuwa Onsen, with a large indoor pool and an open-air bath. Current main official pages do not specify source flow, water addition, heating, circulation or disinfection for each pool.
Bathing indications
The official page positions the bath as a place to soak after a walk by Lake Suwa. Older third-party analysis figures are not substituted for current official spring data.
Source flow and bath-by-bath water-treatment conditions are not published.
The 15 August 2026 closure was a one-day fireworks-event notice, not evidence of a continuing closure in September. Large events may still affect hours.
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.
