KaminosekiKaikyoOnsenHatokonoYu

A red hot spring overlooking the Kaminoseki Strait, with stone and wood baths and a low-temperature sauna to enjoy in alternating men’s and women’s bathing areas

Yamaguchi Kaminoseki Town

A natural hot spring facility located at the southern tip of the Murotsu Peninsula in Kaminoseki Town, Kumage District, Yamaguchi Prefecture. Standing just before the bridge over the Kaminoseki Strait, this scenic bathhouse has long been loved by people from the local area and beyond for its open-air bath with sweeping views of the Seto Inland Sea.

Hot Spring & Bath Information

Aka-yu Open-Air Bath

TypeNatural Hot Spring

A distinctive reddish-brown open-air hot spring bath called Aka-yu because its color changes when exposed to air. The natural hot spring water, drawn from 1,000 m underground, reacts with air and oxidizes iron and manganese, producing its unique color. It is popular for easing lower back pain and helping you stay warm longer after bathing, and you can enjoy the waters in a stunning setting with a panoramic view of the Kaminoseki Strait. Its deep, opaque color conveys the very essence of a hot spring and makes it a symbol of Hatoko no Yu.

Sauna

Low-temperature dry sauna

70°C

Sauna TypeDry Sauna

Stove TypeInfrared Heater

Capacity20people

Men'sWomen's

A spacious dry sauna for 20 people, equipped with an electric stove with far-infrared heating. Set at a low temperature of around 70, it also has a TV and offers a gentle, relaxing environment for long stays. Thanks to the humidity, it feels pleasantly warm, letting you work up a deep sweat over 10 to 15 minutes.

Cold Bath

Cold Bath

17°C

Water QualityTap Water

Capacity4people

Men'sWomen's

A square cold water bath for 4 people placed next to the sauna room. While the water temperature is set at just the right level so even those who dislike cold cold plunge baths can feel comfortable, it still provides a strong tightening effect when paired with the low-temperature sauna.

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

924 Murotsu, Kaminoseki, Kumage District, Yamaguchi 742-1403, Japan

View on Google Maps

Website

https://www.hatokonoyu.jp/
Onsen & Spa Facilities (Super Sento, Sauna, Spa)

Gender Access

Gender Separated

🚫
Tattoo Policy
No Tattoos
Premium Magazine

Japan's Must-Visit Finest Onsen & Sauna Facilities

Curated by an expert who visits onsen and sauna facilities every day and has explored 300+ locations — only facilities confirmed to be truly exceptional are featured.

Learn more