A famous 100% free-flowing natural hot spring and an open-air bath surrounded by the murmur of the Neri River
Gunma Numata City
"Nango Onsen Shakunage no Yu" is a day-use hot spring facility surrounded by the rich natural beauty of Numata City, Gunma Prefecture. It offers luxurious alkaline simple hot spring water from a source that gushes out at nearly 400 liters per minute on the premises, served as 100% free-flowing natural spring water with no added water, no heating, and no recirculation. The fresh, faintly sulfur-scented water has a smooth, silky feel with a pH of 9.4. The sauna is a dry type with a pleasantly steady heat, and it pairs perfectly with the crisp, cold plunge bath. In the open-air bath, where you can hear the murmur of the Neri River, you can spend a soothing time gazing at the deep mountain scenery and feeling as though your body and mind are becoming one with nature.
TypeNatural Hot Spring
An alkaline simple hot spring with a pH of 9.4, gushing from the premises. Committed to 100% free-flowing natural spring water with no added water or heating, it lets you experience the full power of the spring directly. The colorless, clear water with a faint sulfur scent is a skin-smoothing beauty bath. You can fully enjoy this fresh famous hot spring in a variety of baths with different atmospheres, such as cypress baths and stone baths.
Sauna TypeDry Sauna
Stove TypeConvection Stove (Sauna Stone)
Capacity6people
A compact, calm dry sauna wrapped in the warmth of wood. The steady heat generated by convection-style sauna stones warms the room evenly and encourages a comfortable sweat. In this quiet space with no TV, you can relax while focusing on your own breathing. Outdoor bathing in the open-air area just outside the sauna room brings exceptional totonou.
Water QualityTap Water
Capacity4people
A cold plunge bath prized for its sharp, refreshing chill, designed to quickly cool down a body heated by the sauna. The clean water has a crisp feel on the skin and is full of refreshing clarity. With enough depth to immerse your whole body, it lets you cool down thoroughly. Feeling the open-air breeze while being wrapped in fresh water adds even more depth to the sauna experience.
Closed Days: Thursday
100 Nango, Hikage, Tone-machi, Numata-shi, Gunma 378-0313
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
A famous 100% free-flowing natural hot spring and an open-air bath surrounded by the murmur of the Neri River
Gunma Numata City
"Nango Onsen Shakunage no Yu" is a day-use hot spring facility surrounded by the rich natural beauty of Numata City, Gunma Prefecture. It offers luxurious alkaline simple hot spring water from a source that gushes out at nearly 400 liters per minute on the premises, served as 100% free-flowing natural spring water with no added water, no heating, and no recirculation. The fresh, faintly sulfur-scented water has a smooth, silky feel with a pH of 9.4. The sauna is a dry type with a pleasantly steady heat, and it pairs perfectly with the crisp, cold plunge bath. In the open-air bath, where you can hear the murmur of the Neri River, you can spend a soothing time gazing at the deep mountain scenery and feeling as though your body and mind are becoming one with nature.
TypeNatural Hot Spring
An alkaline simple hot spring with a pH of 9.4, gushing from the premises. Committed to 100% free-flowing natural spring water with no added water or heating, it lets you experience the full power of the spring directly. The colorless, clear water with a faint sulfur scent is a skin-smoothing beauty bath. You can fully enjoy this fresh famous hot spring in a variety of baths with different atmospheres, such as cypress baths and stone baths.
Sauna TypeDry Sauna
Stove TypeConvection Stove (Sauna Stone)
Capacity6people
A compact, calm dry sauna wrapped in the warmth of wood. The steady heat generated by convection-style sauna stones warms the room evenly and encourages a comfortable sweat. In this quiet space with no TV, you can relax while focusing on your own breathing. Outdoor bathing in the open-air area just outside the sauna room brings exceptional totonou.
Water QualityTap Water
Capacity4people
A cold plunge bath prized for its sharp, refreshing chill, designed to quickly cool down a body heated by the sauna. The clean water has a crisp feel on the skin and is full of refreshing clarity. With enough depth to immerse your whole body, it lets you cool down thoroughly. Feeling the open-air breeze while being wrapped in fresh water adds even more depth to the sauna experience.
Closed Days: Thursday
100 Nango, Hikage, Tone-machi, Numata-shi, Gunma 378-0313
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