Enjoy a rich amber-colored beauty spring with 100% free-flowing natural spring water
Niigata Tokamachi City
"Senju Onsen Sennen no Yu" is a luxurious day-use hot spring in Tokamachi City, Niigata Prefecture, offering 100% free-flowing natural spring water. Its mildly alkaline sodium bicarbonate and chloride spring is known as a rich amber beauty bath with a silky-smooth feel. The bathing area features a hinoki cypress bath and a stone bath that alternate weekly between men and women, along with a spacious open-air bath and tsuboyu pot baths made with Shigaraki ware, letting you enjoy the famous waters in a variety of styles. It also has a high-temperature dry sauna and a cold plunge bath fed by continuously flowing underground water, making for a fulfilling totonou experience that is also popular with sauna enthusiasts.
TypeNatural Hot Spring
Sodium bicarbonate and chloride spring (mildly alkaline, hypotonic, high-temperature spring). Renowned as a beauty bath, it is characterized by a silky bathing feel. All baths are supplied with 100% free-flowing natural spring water without any added water, making it a truly luxurious hot spring.
Sauna TypeDry Sauna
Stove TypeConvection Stove (Sauna Stone)
Capacity6people
A high-temperature dry sauna. It is small, accommodating around 6 people, but you can still feel the intense heat. In a calm space loved by locals, you can slowly work up a good sweat.
Water QualityNatural Water (Groundwater, Spring, etc.)
Capacity2people
A pleasantly refreshing cold plunge bath using underground water except during the winter season. It stays thoroughly cold at around 15°C and quickly tightens the body after sauna use. The cool-down is especially appealing for its crisp, clean feel, unique to underground water.
Closed Days: None
948-0144 Niigata Prefecture, Tokamachi City, Mizuguchizawa 121-7
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 a rich amber-colored beauty spring with 100% free-flowing natural spring water
Niigata Tokamachi City
"Senju Onsen Sennen no Yu" is a luxurious day-use hot spring in Tokamachi City, Niigata Prefecture, offering 100% free-flowing natural spring water. Its mildly alkaline sodium bicarbonate and chloride spring is known as a rich amber beauty bath with a silky-smooth feel. The bathing area features a hinoki cypress bath and a stone bath that alternate weekly between men and women, along with a spacious open-air bath and tsuboyu pot baths made with Shigaraki ware, letting you enjoy the famous waters in a variety of styles. It also has a high-temperature dry sauna and a cold plunge bath fed by continuously flowing underground water, making for a fulfilling totonou experience that is also popular with sauna enthusiasts.
TypeNatural Hot Spring
Sodium bicarbonate and chloride spring (mildly alkaline, hypotonic, high-temperature spring). Renowned as a beauty bath, it is characterized by a silky bathing feel. All baths are supplied with 100% free-flowing natural spring water without any added water, making it a truly luxurious hot spring.
Sauna TypeDry Sauna
Stove TypeConvection Stove (Sauna Stone)
Capacity6people
A high-temperature dry sauna. It is small, accommodating around 6 people, but you can still feel the intense heat. In a calm space loved by locals, you can slowly work up a good sweat.
Water QualityNatural Water (Groundwater, Spring, etc.)
Capacity2people
A pleasantly refreshing cold plunge bath using underground water except during the winter season. It stays thoroughly cold at around 15°C and quickly tightens the body after sauna use. The cool-down is especially appealing for its crisp, clean feel, unique to underground water.
Closed Days: None
948-0144 Niigata Prefecture, Tokamachi City, Mizuguchizawa 121-7
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