Zao Onsen, Yamagata
Yunohana Chaya Shinzaemon-no-Yu
A well-equipped day-use bathhouse with outdoor pools, a rest area and dining. The outdoor baths use Zao's strongly acidic sulfur spring, while the indoor bath is an artificial alkaline mineral bath. Tattoos are explicitly prohibited, with no covering exception.
Check before bathing
- Opening hours
- 10:00–18:00; last admission 17:30. Adult ¥1,000, elementary-school age ¥400, preschool age three and up ¥200. No private bath. A single-person reservation-box sauna is available separately and is not a private onsen.
- Tattoo policy
- Entry is refused for tattoos, tattoo-like marks and body paint, regardless of style or how they were applied. No covering exception is stated.
Spring & water temperature
- Spring-source temperature
- Not published for this facility.
- Bathing temperature
- Not published by pool.
- Spring source
- Zao Onsen's strongly acidic sulfur spring; a current individual source name was not published in the main official pages reviewed.
- Spring classification
- Acidic sulfur-bearing aluminum sulfate-chloride spring system; the individual facility's latest analysis sheet was not confirmed.
- pH
- Not published for this facility; do not substitute the area-wide figure.
- Flow rate
- Not published for this facility.
- Water handling
- The facility identifies its outdoor baths as 100% source water. The indoor bath is an artificial alkaline mineral bath, so not all pools share the same spring or treatment. Pool-specific temperatures and full treatment details are not published.
Bathing indications
The operator lists general bathing indications for the spring, including cuts, burns, chronic skin conditions and hypertension. These are not a promise of medical benefit.
There is no private bath. The reservation-only box sauna is for one person and is not a private onsen.
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.
