Hinodeyu in Inaricho: Ancient Hinoki, Natural Spring Water and a Weekly Floor Change

Hinodeyu’s signature bath is made from hinoki said to be more than 1,000 years old. It is a modest neighbourhood sento near Inaricho Station, not a large sauna complex, and its natural spring has a useful backstory: a well long treated as groundwater was later found to meet Japan’s legal definition of a hot spring because of its metasilicic acid content.

A spring-water detail worth getting right

Tokyo’s environmental council records the well at about 120 metres deep, with source water at 17.8°C. It has no formal spring-type name, but metasilicic acid meets the legal threshold for classification as a hot spring. The council document also describes a pumping permit and planned pumping volume; those figures are not the same as a naturally flowing spring yield, so they should not be presented as one.

Hinodeyu says it uses natural spring water without filtration. The hot bath water is heated; the 17.8°C figure is the source temperature, not the temperature of the bathing pools. The name “natural hot spring” reflects the water’s legal classification, not a hot source rising from the ground.

The ancient-hinoki tub is the other reason to come. Hinodeyu says the wood is over a thousand years old. Compared with a tiled bath, the surface feels different under hand and foot, and the inn says the wood can make the water feel a little gentler. It is an older, well-used tub, not a newly built spa feature; take care on wet wood when getting in or out.

The floor determines the extra feature

The first- and second-floor baths change between men and women each week. Both sides have the core hot-spring and hinoki bathing, but the first floor has a small steam sauna, while the second has an open-air-style rock bath. The steam sauna is around 45°C, fits one person and is free when your side is on the first floor. It is a gentle steam room, not a high-temperature dry sauna.

There is no permanent cold plunge. Hinodeyu sometimes converts the second-floor outdoor bath into a seasonal cold bath for about two weeks in summer, but that is not a year-round feature. Check the current exchange calendar before going if the sauna or rock bath is the main reason for your visit.

What to know before you go

Bring shampoo and body wash or buy them at reception; none are supplied in the bath area. Tattoos are allowed under Hinodeyu’s published FAQ. The building asks guests to keep visits within two hours.

Hinodeyu also has a small sento café counter; its official page says drinks can be purchased without bathing. For a larger men’s sauna setup nearby, compare Shiromizuyu in Iriya. If you are deciding between different Asakusa-area baths, Yudonburi Sakaeyu has a much more equipment-heavy natural-spring experience.

Sources

- [Hinodeyu: official site, hours and facility notes](https://hinodeyu.com/) - [Hinodeyu: weekly first-/second-floor rotation](https://hinodeyu.com/1fchange2f/) - [Hinodeyu: access](https://hinodeyu.com/access/) - [Hinodeyu: sento café](https://hinodeyu.com/asakusa-sento-cafe/) - [Tokyo Metropolitan Environmental Council: Hinodeyu well and spring classification](https://www.kankyo.metro.tokyo.lg.jp/documents/d/kankyo/02-12-21gijiroku-1-) - [Taito Sento: Hinodeyu and rental set information](https://www.taitosento.com/hinodeyu/) - [Tokyo Sento Association: 2026 adult bathing fee](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: 2026-09-27

Tags: Hinodeyu, Inaricho sento, natural hot spring in Tokyo, ancient hinoki bath, Ueno bathhouse