Hanno Onsen
- Location
- Hanno, Saitama, Kanto, Japan
- Water type
- sodium chloride
- Temperature
- 41 °C
- pH
- 7.3
Water profile
Relaxing — deep, immediate muscle release.
Loaded with major ions — the essential minerals (Ca, Mg).
Dense, salty water — you float without effort.
Hanno Onsen serves a city at the western edge of Saitama Prefecture where the Agano River valley opens into the forested foothills of Chichibu-Tama-Kai National Park, providing Tokyo-area residents with one of their most accessible gateways to genuine mountain hiking, river kayaking, and the extraordinary bamboo and cedar forests of Oku-Musashi. The area's character is that of a transitional zone between the urban and the truly wild, where department stores and suburban housing estates give way within minutes to mountain trails leading to peaks with sweeping views across the Kanto Plain and toward Mount Fuji. The onsen's geothermal mineral waters, rising from the folded metamorphic rocks of the Chichibu belt, offer genuine mountain spring quality remarkably close to the largest urban concentration in human history.