Enjoy panoramic views of the five peaks of northern Shinshu and the hot spring's day-to-day changing water colors
Nagano Obuse Town
Obuse Onsen Akebi no Yu, located in Obuse Town, Nagano Prefecture, is a facility proud of its scenic open-air bath overlooking the five peaks of northern Shinshu and a mysterious natural hot spring whose color changes with weather conditions. It features a firmly hot 95℃ dry sauna and a 15–18℃ free-flowing cold plunge bath repurposed from a household bathtub, allowing you to fully enjoy both the onsen and the sauna.
TypeNatural Hot Spring
A sulfur-containing calcium–sodium chloride spring. Depending on weather conditions the water can change from colorless and transparent to green or milky white, and dark mineral particles float through the bath, making it a high-quality hot spring.
Sauna TypeDry Sauna
Stove Typeelectric
Capacity8people
A dry sauna equipped with a convection stove, approximately 88–95℃. The subdued lighting creates a calm space where you can really feel the heat.
Water Qualitynatural_water
Capacity1people
A single-person cold plunge bath made from a household bathtub, retrofitted into the standing-shower area. Tap water (natural spring water) is continuously poured from the faucet, and in winter it becomes well chilled to 15℃ or below.
Closed Days: None
1311 Fudo, Karita, Obuse-machi, Kamitakai-gun, Nagano 381-0211, Japan
Gender Access
Gender Separated
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
Enjoy panoramic views of the five peaks of northern Shinshu and the hot spring's day-to-day changing water colors
Nagano Obuse Town
Obuse Onsen Akebi no Yu, located in Obuse Town, Nagano Prefecture, is a facility proud of its scenic open-air bath overlooking the five peaks of northern Shinshu and a mysterious natural hot spring whose color changes with weather conditions. It features a firmly hot 95℃ dry sauna and a 15–18℃ free-flowing cold plunge bath repurposed from a household bathtub, allowing you to fully enjoy both the onsen and the sauna.
TypeNatural Hot Spring
A sulfur-containing calcium–sodium chloride spring. Depending on weather conditions the water can change from colorless and transparent to green or milky white, and dark mineral particles float through the bath, making it a high-quality hot spring.
Sauna TypeDry Sauna
Stove Typeelectric
Capacity8people
A dry sauna equipped with a convection stove, approximately 88–95℃. The subdued lighting creates a calm space where you can really feel the heat.
Water Qualitynatural_water
Capacity1people
A single-person cold plunge bath made from a household bathtub, retrofitted into the standing-shower area. Tap water (natural spring water) is continuously poured from the faucet, and in winter it becomes well chilled to 15℃ or below.
Closed Days: None
1311 Fudo, Karita, Obuse-machi, Kamitakai-gun, Nagano 381-0211, Japan
Gender Access
Gender Separated
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