Nishikamata, Ota, Tokyo
Kaiseiyu
A classic Tokyo sento for black spring water, a black-water carbonated bath and a distinctive fish tank. It has no sauna, so sauna regulars should choose another bathhouse.
Check before bathing
- Opening hours
- 15:00–23:30; closed Fridays. Adult admission is ¥600 under Tokyo's rate from 2026-08-01. A hands-free set is listed at ¥220 in current secondary facility information, in addition to admission.
- Access
- About a 7–8-minute walk from JR or Tokyu Kamata Station.
- Tattoo policy
- A current first-party tattoo rule was not found in the material reviewed; call ahead if this affects your visit.
Spring & water temperature
- Spring-source temperature
- Not published in current first-party information.
- Bathing temperature
- The black-water carbonated bath is about 39–39.5°C according to Ota City; fixed temperatures for the other black-water pools are not published.
- Spring classification
- Natural black mineral water, commonly classified in secondary sources as a sodium bicarbonate cold mineral spring. The facility's latest complete analysis sheet was not available, so that classification is not treated as a current official analysis.
- pH
- Not published in current first-party information.
- Flow rate
- Not published.
- Water handling
- Natural black water is used in the regular black-water bath, black-water carbonated bath and black-water cold bath. Carbon dioxide is added artificially to the carbonated pool. Current first-party text does not detail water addition, heating, circulation, disinfection or source-flowing conditions by pool.
Older opening-hour listings and sauna references are stale; current materials describe no sauna.
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.
