A spa resort featuring natural hot spring water flowing directly from the source and a high-temperature sauna
Gunma Shibukawa City
"Akagi Natural Hot Spring Hanyu Utopia Akagi" is a day-use hot spring facility in Shibukawa, Gunma Prefecture. Located in an open area along the Tone River, it offers natural weakly alkaline hot spring water bubbling up from deep underground, enjoyed as free-flowing spring water straight from the source. The sauna is set to a high temperature, and the facility recommends mokushou, a quiet, meditative experience where you face yourself in a tranquil space. The cold plunge bath uses natural water, with a smooth, gentle feel on the skin and a pleasantly cooling effect that softly soothes your overheated body. It also features a fitness gym, a warm-therapy cafe lounge, and a rock bath, making it a resort complex where you can spend the entire day in a healthy way.
TypeNatural Hot Spring
A weakly alkaline simple hot spring that bubbles up from underground. It has little stimulation and feels gentle on the skin, and the open-air bath lets you enjoy fresh spring water directly from the source. It is highly heat-retaining, so you stay warm for a long time and do not cool down easily after bathing. The spacious tubs let you relax and unwind while feeling the air at the foot of Mount Akagi.
Sauna TypeDry Sauna
Capacity8people
A dry sauna characterized by its high-temperature setting. The compact L-shaped room offers a quiet, TV-free space where you can enjoy mokushou and work up a deep sweat at a leisurely pace. The heat circulates well, giving you the feeling of warming up from the core even in a short time. The calm lighting creates an environment where you can focus and fully engage with the sauna.
Water QualityNatural Water (Groundwater, Spring, etc.)
Capacity2people
A cold plunge bath using natural water. The water quality is exceptionally smooth and gentle on the skin, with a soothing sense of freshness that feels as if it wraps around you. Fresh water continuously flows in, and the cleanliness is outstanding. Its moderate temperature helps gently yet effectively cool down your overheated body after the sauna.
Closed Days: None
850-3 Miyata, Akagimachi, Shibukawa-shi, Gunma 379-1121
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 spa resort featuring natural hot spring water flowing directly from the source and a high-temperature sauna
Gunma Shibukawa City
"Akagi Natural Hot Spring Hanyu Utopia Akagi" is a day-use hot spring facility in Shibukawa, Gunma Prefecture. Located in an open area along the Tone River, it offers natural weakly alkaline hot spring water bubbling up from deep underground, enjoyed as free-flowing spring water straight from the source. The sauna is set to a high temperature, and the facility recommends mokushou, a quiet, meditative experience where you face yourself in a tranquil space. The cold plunge bath uses natural water, with a smooth, gentle feel on the skin and a pleasantly cooling effect that softly soothes your overheated body. It also features a fitness gym, a warm-therapy cafe lounge, and a rock bath, making it a resort complex where you can spend the entire day in a healthy way.
TypeNatural Hot Spring
A weakly alkaline simple hot spring that bubbles up from underground. It has little stimulation and feels gentle on the skin, and the open-air bath lets you enjoy fresh spring water directly from the source. It is highly heat-retaining, so you stay warm for a long time and do not cool down easily after bathing. The spacious tubs let you relax and unwind while feeling the air at the foot of Mount Akagi.
Sauna TypeDry Sauna
Capacity8people
A dry sauna characterized by its high-temperature setting. The compact L-shaped room offers a quiet, TV-free space where you can enjoy mokushou and work up a deep sweat at a leisurely pace. The heat circulates well, giving you the feeling of warming up from the core even in a short time. The calm lighting creates an environment where you can focus and fully engage with the sauna.
Water QualityNatural Water (Groundwater, Spring, etc.)
Capacity2people
A cold plunge bath using natural water. The water quality is exceptionally smooth and gentle on the skin, with a soothing sense of freshness that feels as if it wraps around you. Fresh water continuously flows in, and the cleanliness is outstanding. Its moderate temperature helps gently yet effectively cool down your overheated body after the sauna.
Closed Days: None
850-3 Miyata, Akagimachi, Shibukawa-shi, Gunma 379-1121
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