Ojima Onsen
- Location
- Ojima, Ota, Gunma, Japan
- Water type
- sodium chloride
- Temperature
- 42 °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.
Ojima Onsen draws visitors to Ito on the Izu Peninsula, a town whose deepest historical layer is the remarkable story of William Adams — the English navigator who arrived in Japan in 1600, became the first Western samurai, and served as a trusted advisor to Tokugawa Ieyasu, the shogun who unified Japan. Adams, known in Japan as Miura Anjin, built Western-style ships in Ito for the Tokugawa regime, and the town celebrates his legacy each August with the Anjin Festival, complete with period costumes and maritime pageantry. The onsen's mineral-rich waters, typical of the Izu Peninsula's exceptional geothermal abundance, provide restorative bathing in a town where East and West first met in extraordinary historical circumstances.