Cold water plunge bath, typically used after sauna
Capabilities
Private BathNo
Private bath available for day-use visitors or hotel guests to reserve
Mixed BathingYes
Shared bathing area for all genders
A bathing garment (yuami-gi, 湯浴み着) or swimsuit is required for mixed bathing.
Policies & Services
WashingYes
Shower, wash stations, soap and shampoo provided
TowelsYes
Towels available to rent or borrow
Rest AreaYes
Relaxation space for after bathing
ParkingYes
On-site or nearby parking available
About
The stone-garden open-air bath (sekitei rotenburo, 石庭露天風呂) is the reason to come here, eight pools fed by four distinct springs, most of them mixed-gender, with water ranging from the classic milky-white sulfur through a rare fluorescent yellow to clear. The sulfur content is about 27 times the standard threshold, and the mountain setting at over 1,800 meters adds to the atmosphere.
I was there for a higaeri visit, and ended up with a private bath for one person :)
Probably the place with the richest variety of baths and spring sources for konyoku, a unique spot. There are 4 different sources right away, and they are noticeably different. The baths also vary in temperature and size. There is a bit of a view of the mountains and the river, but mostly it is the pleasant sound from the river.
As a konyoku place, it is very welcoming to beginners, you can go in special clothing and with towels rented at the entrance.
If you are staying at the nearby Prince Hotel, you can come here for free.
2026.1
812. Manza Kogen Hotel, Manza Onsen, Gunma ★★★
I visited the main open-air mixed bathing area on a day-trip basis, 7 baths (the 8th listed bath is available only for women). For guests staying at Manza Prince Hotel, day-trip bathing is free. With the Manza tegata, it is ¥500, the regular price is ¥1 700. Day-trip bathing is listed from 11:00 to 18:00 (last entry at 17:00).
For overnight guests, there are also additional non-mixed baths, one indoor bath and one open-air bath for each gender. As I understood it, the mixed open-air bath area has the same schedule for overnight guests as it does for day-trip visitors. Staying at Manza Kogen Hotel should also give you free day-trip bathing at Manza Prince Hotel.
Open-air mixed bathing area. They provide and require clothing. Views of the mountains, hotel buildings, snow, and trees. The bath area feels a bit chaotic and underground, with some cones, barriers, chains, and no extra polish, but that gives the place its own authentic atmosphere.
The baths to the left of the exit from the men's changing room, from left to right:
1. Small rectangular bath. It was closed. The water was clear blue, with lime deposits.
2. Small bath partly in rock. The water was clear blue, temperature 44.5.
3. Bath in rock. The water was clear blue, with a lot of lime at the spring source on the bottom. Temperature 43.5.
4. Bath in rock. The water was cloudy blue, temperature 44.
Center:
5. Bath in rock in the center. The water was cloudy green. By feel, it was the most acidic, my skin tingled more noticeably than in the others. Temperature 44.5.
The farther baths from the exit of the men's changing room:
6. Bath in rock. The water was clear blue, temperature 43.5.
7. Small bath in rock. The water was clear turquoise. Temperature 45.5.
A large open mixed bathing area in a snowy hollow, rock baths with four types of water at different temperatures and appearances. This is a top-tier place, really great.
15.01.2026
