Hottayu in Nishiarai: Herbal Sauna and a 1.6-Metre Cold Plunge
Hottayu pairs a renovated Tokyo sento with herbal auto-roulyu and outdoor baths. Compare its 1.6-metre men’s plunge and sauna fees by side.
Hottayu has been part of Nishiarai since 1942. Its 2022 renovation kept the traditional bathhouse building and the tile mural, then added an outdoor bathing area and a sauna circuit that has become its main draw. The most unusual detail is on the men’s side: an outdoor cold plunge deep enough for many adults to stand in almost to the shoulders.
A sauna shaped around herbal steam
The sauna uses automatic water-pouring and herbal aromatics; its draw is the changing steam and scent rather than a published fixed temperature. Hottayu does not list a permanent sauna temperature, and readings from individual visits should not be treated as a year-round setting.
The men’s side has a 160-centimetre-deep outdoor cold bath and a spacious outdoor-air rest area. The women’s side has two cold baths at different temperatures instead. The layout is not identical, so check the side-specific details if you are visiting for one particular plunge.
Hottayu is not listed as a natural hot spring. Its appeal is the contrast between the old bathhouse frontage and a contemporary sauna circuit, not spring-water credentials.
Fees, hours and access
| Item | Men | Women |
|---|---|---|
| Bath admission | ¥600 | ¥600 |
| Sauna add-on | ¥500 | ¥350 |
| Bath and sauna | ¥1,100 | ¥950 |
| Hands-free set (bath, sauna, shampoo and body wash) | ¥1,500 | ¥1,350 |
Shampoo and body wash are not stocked free in the bathing area, but are included in the hands-free set or available to buy.
Weekday hours are 2 p.m.–midnight; Saturdays, Sundays and public holidays open from 8 a.m. The regular closing day is the second Thursday of each month. Nishiarai Station on the Tobu Skytree Line is about a seven-minute walk away. There are seven paid parking spaces nearby according to the facility.
The morning opening is a weekend feature, not a weekday one. Hottayu can get busy in the evening and on weekends, so allow extra time if using the sauna is the point of the visit. Tattoos are not clearly addressed on its public facility page; check directly before setting out if you need a definite answer.
For a bathhouse built around a different kind of sauna experience, compare Egotayu in Nakano.
Sources
- [Hottayu: current fees, hours, baths and access](https://www.4126.tokyo/) - [Tokyo Sento Association: Hottayu renovation feature](https://www.1010.or.jp/mag-lens-44-hottayu/) - [Tokyo Sento Association: adult bathing fee from August 1, 2026](https://www.1010.or.jp/guide/%E5%85%A5%E6%B5%B4%E6%96%99%E9%87%91%E3%81%AE%E3%81%8A%E7%9F%A5%E3%82%89%E3%81%9B/) Checked: 2026-09-27Tags: Hottayu, Nishiarai sento, Tokyo herbal sauna, deep cold plunge
