Inunakiyama Onsen
- Location
- Izumisano, Osaka, Japan
- Water type
- thermal
- Temperature
- 38 °C
- pH
- 7.3
Water profile
Soothing — neither hot nor cold, perfect balance.
Rich in trace elements — gentle on the skin.
Soft water — natural, classic buoyancy.
Inunakiyama Onsen is the sole onsen cluster within Osaka Prefecture, tucked into the mountain valley of Izumisano City where the Kashii River flows through a landscape opened as a shugendo ascetic practice site over 1,300 years ago—a spiritual heritage that suffuses the spring with the contemplative atmosphere of mountain Buddhist practice unique within Japan's most densely urban prefecture. Three inns line the river canyon alongside the central Yamanoya bath facility, preserving a community-scale thermal tradition that exists nowhere else within the vast metropolitan sprawl of the Kansai region. The spring's name references the Inunaki legend—a tale from around 960 CE of a loyal dog who saved its master's life in these mountains—giving this remote Osaka highland spring an unexpected layer of folklore and historical depth.