MutsuzawaOnsenTsudoinoYu

Enjoy a full-fledged sauna and a famous hot spring at a roadside station where ancient fossil seawater springs forth

Chiba Mutsuzawa

"Mutsuzawa Onsen Tsudoi no Yu" is a day-use hot spring facility attached to the roadside station Mutsuzawa Tsudoi no Sato in Mutsuzawa Town, Chiba Prefecture. Its pride is the natural hot spring drawn from brine, a fossil seawater rich in iodine, buried deep underground in ancient strata. There is also a continuously flowing bath using water straight from the source in the indoor bath, and the distinctive aroma and silky water soothe and warm the body from the core. The sauna is alternated weekly between men and women, with a dry sauna equipped with auto-löyly and a mist sauna full of gentle moisture. The cold plunge bath is crisp and cold, refreshing and tightening the body after sauna. With fresh local ingredients and a spacious relaxation area that are unique to a roadside station, it is also a popular destination for a drive.

Hot Spring & Bath Information

Mutsuzawa Onsen

TypeNatural Hot Spring

Flow-through

A natural hot spring rich in iodine, drawn from brine, a fossil seawater from ancient times. The amber-colored water has a high salt concentration and offers exceptionally strong warming and moisturizing effects. In the indoor bath’s continuously flowing tub with water straight from the source, you can feel the power of the fresh water against your skin. Its distinctive aroma and silky texture soothe both body and mind, easing fatigue from the roots.

Sauna

Dry Sauna

90°C

Sauna TypeDry Sauna

Stove TypeConvection Stove (Sauna Stone)

Capacity15people

Men'sWomen's

A full-fledged dry sauna installed on one side of the bath area, which alternates weekly between men and women. Using sauna stones in a convection-style setup, auto-löyly is performed every 30 minutes, sending pleasant waves of heat through the room. With excellent heat circulation, you can experience high-quality sweating. It is a space where you can relax, watch TV, and work up a refreshing sweat at your own pace.

Mist Sauna

50°C

Sauna TypeMist Sauna

Capacity8people

Men'sWomen's

A mist sauna installed on the other side of the bath area, which alternates weekly between men and women, filled with soft steam. It gently warms the body at a low temperature, allowing you to relax while hydrating the skin. Easy for those who do not like dry saunas to enter, it offers the appeal of quietly unwinding both body and mind.

Cold Bath

Cold Bath

17°C

Water QualityNatural Water (Groundwater, Spring, etc.)

Capacity3people

Men'sWomen's

A cold plunge bath located right near the sauna room. Its crisp, cold temperature quickly tightens the body after sauna. The water feels pleasant on the skin, and the depth is ample, making efficient cool-down possible. Even in alternating hot-and-cold bathing with the natural hot spring, you can fully enjoy its refreshing sensation.

Business Hours

Monday
10:00〜21:00
Tuesday
10:00〜21:00
Wednesday
10:00〜21:00
Thursday
10:00〜21:00
Friday
10:00〜21:00
Saturday
10:00〜21:00
Sunday
10:00〜21:00
Holiday
10:00〜21:00

Closed Days: None

Address

299-4422 2-1 Mori, Mutsuzawa Town, Chosei District, Chiba Prefecture

View on Google Maps

Website

https://mutsuzawa-swt.jp/facility_onsen
Onsen & Spa Facilities (Super Sento, Sauna, Spa)

Gender Access

Gender Separated

❓
Tattoo Policy
Unknown (Please Check)
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