Uchinomaki Onsen, Aso, Kumamoto
Hotel Kadoman
A budget-friendly option if you want outdoor bathing, a cave-style bath and a private family bath under one roof. Day-use is offered on an irregular schedule, so call before setting out. The source is described as a sulfate spring and source-flowing, while fixed treatment details are not published for every pool.
Facility photos
Check before bathing
- Opening hours
- 15:00–22:00; irregular closing days. Public bath: ¥500 for ages 6 and up, ¥300 for ages 3 to under 6. Six family baths are listed at ¥2,500 for 60 minutes; confirm same-day availability.
Spring & water temperature
- Spring-source temperature
- 45°C, according to the facility FAQ updated February 14, 2026.
- Bathing temperature
- 38–42°C, according to the facility FAQ updated February 14, 2026.
- Spring source
- Hotel Kadoman's spring; the individual source name is not published.
- Spring classification
- Sulfate spring.
- pH
- Not published.
- Flow rate
- Not published.
- Water handling
- The Aso inn association describes the water as 100% natural hot spring and source-flowing. A facility FAQ updated February 14, 2026 says no dilution and no heating; full pool-by-pool treatment details are not published.
Day-use and private-bath availability depend on the inn's schedule and vacancies.
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.
