Hakuju no Yu in Saitama: A Dark Mineral Spring and a Slow Afternoon
Plan a visit to Ofuro Cafe Hakuju no Yu in Kamikawa. Check current admission, the mineral-rich spring, lounge and food options, bus access and tattoo rules.
Hakuju no Yu is in Kamikawa, near the Saitama–Gunma border. The source rises from about 750 metres below ground and is a sodium-chloride strong-saline spring. The bathhouse says the water is diluted with well water, heated and circulated; after heating and exposure to air, it becomes a cloudy reddish brown. That mineral character is the main reason to visit. The cafe-style lounge and fermented-food restaurant give you something to do after bathing, but they do not make the trip short or station-adjacent.
Check the ticket and how long you plan to stay
The current operator listing shows:
| Entry period | Adult | Child |
|---|---|---|
| Weekday, 10 a.m.–9 p.m. | ¥880 | ¥450 |
| Saturday, Sunday and public holiday, 10 a.m.–9 p.m. | ¥1,130 | ¥450 |
| Any day, 9–10:30 p.m. night rate | ¥580 | ¥300 |
The facility closes at 11 p.m.; last entry is 10:30 p.m. Children under three enter free. Towels and indoor clothing are not included: the current page lists each rental at ¥380. The operator announced special Silver Week prices for September 2026, but the readable notice did not state the amounts; use the current notice for any special period rather than assuming the regular weekend rate.
If you only want the spring, the standard bathing ticket is enough. Allow two or three hours if you also want to sit in the lounge, read, or eat; the discounted late-night ticket gives you a short final bathing window, not a full afternoon at the property.
The water changes colour, and the operator explains why
The spring is described as a high-salinity sodium-chloride hot spring from an ancient geological layer. The operator says it is clear when first drawn, then becomes opaque and reddish brown after contact with air and heating. It also says well water is added to reduce the concentration and help prevent pipe blockage and discomfort from bathing in the undiluted source. Its bathing information lists heating, dilution and recirculation, so do not describe the baths as undiluted or 100% free-flowing.
The operator lists an outdoor bath and a high-temperature indoor bath. It also notes that a koji-containing mud pack is provided in the women’s bathing area. The dark mineral deposits on the bath edges are part of the facility’s spring presentation; they are not evidence of a separate treatment or a guarantee of a specific effect.
There is room to stay after the bath
Hakuju no Yu has a relaxation area with books and magazines, hammock-style seating, massage chairs, free coffee, Wi-Fi, power outlets and places to work. A paid private room is listed at ¥1,000 per hour and must be arranged by phone.
The restaurant, Tawara-ya, serves koji-based dishes and fermented foods; its current page lists food and drink service from 11 a.m. through a 9:30 p.m. last order. A June 2024 renovation added the post-bath lounge and experience spaces. In May 2026, the restaurant refreshed its menu around koji, sleeping brown rice and ingredients from Saitama and Gunma. That is the “new generation” angle: the spring stayed central, while the hours after bathing gained a clearer purpose.
That combination makes a longer stop more sensible than dropping in for a quick bath. If you arrive with only an hour before the return bus, most of the lounge and meal offer will go unused. The broad Tokyo new-generation onsen guide compares this kind of long-stay bathhouse format with city locations; for a closer Saitama option, the Omiya day-use onsen guide covers urban facilities.
Getting there takes planning
By car, the operator gives a drive of about 25 minutes from the Honjo-Kodama interchange. By bus, it lists two approaches: board at Honjo Station’s south exit, or walk about five minutes from Tansho Station to the Tansho-ekiguchi stop. Take a bus toward Kannaizumi General Branch and get off at Shimowatase Asahi Kogyo-mae. The operator links to the bus company and specifically advises checking the current timetable there.
This is a reasonable stop when you are already touring northern Saitama or driving between Saitama and Gunma. It is a poor last-minute choice if you are relying on an infrequent bus and have not checked the return service. Do not assume the bath’s 11 p.m. closing means public transport will still be running.
Rules to check before you go
At Hakuju no Yu, tattoos and body art are not allowed; covering them does not create an exception. Entry is also refused to intoxicated guests and people with contagious illnesses. Children in diapers may use only the baby bath. These rules apply to this branch and may differ at other Ofuro Cafe locations.
