Oshio Onsen
- Location
- Oshio, Fukushima Prefecture, 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.
Oshio Onsen in Kanayama town, Ōnuma District, Fukushima Prefecture, Japan, is a hot spring resort with sulfated saline mineral waters in the mountainous Aizu region of western Fukushima, where the remote Oku-Aizu highlands — one of Japan's most traditionally preserved farming and craft regions — harbor numerous high-quality onsen in the landscape of deep snow, kayabuki (thatched-roof) farmhouses, and dense beech forests of the Tohoku interior. The Aizu region of Fukushima is one of Japan's most romanticized historical landscapes, associated with the Byakkotai — the White Tiger Unit of young Aizu samurai who died in the Boshin War of 1868 — and with the Tsurunojo Castle city of Aizu-Wakamatsu, and its onsen tradition reflects the deep integration of thermal bathing into the austere and beautiful life of the snowy Tohoku highlands. The sulfated saline waters of Oshio Onsen, drawn from the volcanic and sedimentary geology of the Oku-Aizu mountains, provide a warming and mineral-rich bathing experience particularly prized during the region's long, heavy winters.