Okutoyama Onsen
- Location
- Okutoyama, Aichi, Chubu, Japan
- Water type
- bicarbonate
- Temperature
- 40 °C
- pH
- 8
Water profile
Relaxing — deep, immediate muscle release.
Loaded with major ions — the essential minerals (Ca, Mg).
Soft water — natural, classic buoyancy.
Okutoyama Onsen is a mountain hot spring resort in the forested highlands of Toyota city in Aichi Prefecture — Japan's largest city by area despite being globally known as the headquarters of Toyota Motor Corporation — where the vast rural interior of this remarkable dual-identity city combines automobile industry on the lowland with pristine mountain wilderness in the uplands, and siliceous geothermal waters emerge from the geological basement of the Mikawa Highland in the headwaters of the Yahagi River. The contrast between Toyota city's global industrial identity as the epicenter of Japanese automotive manufacturing and the wild mountain landscapes of its forested interior — including the Obara Washi paper village, famous for its spectacular autumn and spring floral displays — creates one of Japan's most surprising urban geographical paradoxes. Okutoyama Onsen offers siliceous thermal bathing deep in the mountain forests that represent the green, traditional heart of a city that has shaped the global industrial landscape, providing a profound counterpoint to the modernity that Toyota's name evokes worldwide.