Kouunsou

A skin-beautifying inn in Shiobara Onsen where you can enjoy 100% free-flowing spring water from the private source Koun no Yu

Tochigi Nasushiobara City

Kouunsou is a hot spring inn in Nasushiobara City, Tochigi Prefecture, where you can enjoy 100% free-flowing spring water from its abundant private source, Koun no Yu. The hot spring water contains metasilicic acid, a natural moisturizing component, at six times the standard amount (314.7 mg), and it is loved as a silky, exceptional skin-beautifying bath. The inn features a large open-air bath that is among the biggest in Shiobara, as well as a private open-air bath that can be used free of charge as often as you like if it is available, with no reservation required. The gender-separated public baths are equipped with authentic sauna facilities, and you can also enjoy a drinking spring water area where you can sip fresh hot spring water, as well as a foot bath.

Hot Spring & Bath Information

Large Public Bath and Large Open-Air Bath

TypeNatural Hot Spring

Flow-through

Abundant hot spring water flowing at 200 liters per minute from the private source Kouunsou Gensen is used luxuriously as 100% free-flowing spring water, with no heating or recirculation. There is a large open-air bath, among the biggest in Shiobara, with some mixed bathing space, as well as a spacious indoor bath, where you can fully enjoy the silky, superb skin-beautifying waters rich in natural moisturizing metasilicic acid.

Private Bath

TypeNatural Hot Spring

Flow-through

A private bath where you can enjoy a famous free-flowing spring bath in a secluded setting. It comes with an indoor bath and a small open-air bath, and there is plenty of hot spring water. Overnight guests may use it freely at no charge when available, without a reservation, using an internal lock. Enjoy the skin-beautifying water all to yourself with your family or loved ones.

Sauna

Large Public Bath Sauna

90°C

Sauna TypeDry Sauna

Stove TypeConvection Stove (Sauna Stone)

Capacity4people

Men'sWomen's

A compact dry sauna installed in each of the gender-separated public baths. The room temperature is about 90–96°C, offering a proper level of heat that encourages a pleasant sweat. With no TV, it is a quiet space where you can focus on yourself and slowly work up a sweat. There is no cold plunge bath, but you can cool down with a cold shower.

Business Hours

Monday
14:00〜09:00
Tuesday
14:00〜09:00
Wednesday
14:00〜09:00
Thursday
14:00〜09:00
Friday
14:00〜09:00
Saturday
14:00〜09:00
Sunday
14:00〜09:00
Holiday
14:00〜09:00
💡 [Day-use bathing] 14:00–20:00 (Irregular holidays. Acceptance hours may be shortened or suspended depending on crowding, so please confirm in advance.)

Closed Days: None

Address

〒329-2921 Tochigi Prefecture, Nasushiobara City, Shiobara 2340-1

View on Google Maps

Website

https://www.kouunsou.com/
Hotel & Ryokan

Gender Access

Gender Separated

❓
Tattoos in the Communal Bath
Unknown (Please Check)

The above applies to the communal (shared) baths. At facilities with private baths or private saunas, guests with tattoos may still be able to bathe. Please check with the facility for details.

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