Open-AirKobushiHotSpring(RotenKobushinoYu)

Two types of saunas and a single-digit cold plunge bath enjoyed in the great outdoors

Nagano Komagane City

Open-Air Kobushi Hot Spring (Roten Kobushi no Yu) is located in Komagane City, Nagano Prefecture, with excellent access just a 3-minute drive from the Komagane Interchange on the Chuo Expressway. The open-air area features two types of saunas, a Finnish-style barrel sauna and a dry sauna, and a chilling cold plunge bath using groundwater at 8℃ (single-digit) that has been highly praised by sauna enthusiasts. The wood-deck outdoor rest area offers a superb sense of openness.

Hot Spring & Bath Information

Hayataro Hot Spring (Hayataro Onsen)

TypeNatural Hot Spring

An alkaline simple hot spring. Enjoy skin-beautifying waters in two types of open-air baths, a rock bath and a hinoki (cypress) bath.

Sauna

Barrel Sauna

106°C

Sauna TypeDry Sauna

Stove Typeelectric

Capacity6people

Men'sWomen's

A newly installed barrel sauna in the open-air area. The wood-scented space lets you warm up slowly and comfortably.

Dry Sauna

94°C

Sauna TypeDry Sauna

Stove Typeelectric

Capacity3people

Men'sWomen's

A compact dry sauna equipped with a retractable electric heater (Bona Sauna) at the back. You can work up a good sweat at around 82–94°C.

Cold Bath

Cold Plunge Bath

8°C

Water QualityNatural Water (Groundwater, Spring, etc.)

Capacity2people

Men'sWomen's

An open-air cold plunge bath using groundwater. With a single-digit water temperature of 8–10℃, you can also enjoy a waterfall-style plunge where cold water pours over your head.

Business Hours

Monday
11:00〜22:00
Tuesday
11:00〜22:00
Wednesday
11:00〜22:00
Thursday
Closed Days
Friday
11:00〜22:00
Saturday
11:00〜22:00
Sunday
11:00〜22:00
Holiday
11:00〜22:00

Closed Days: Thursday

Address

399-4117 23-170 Akaho, Komagane City, Nagano Prefecture, Japan

View on Google Maps

Website

https://drop-of-alps.com/
Onsen & Spa Facilities (Super Sento, Sauna, Spa)

Gender Access

Gender Separated

❓
Tattoo Policy
Unknown (Please Check)
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