A traditional ryokan adjacent to Nibukawa Gorge in Tamagawa-cho, Imabari City, Ehime Prefecture. Nibukawa Onsen is one of the three great hot springs of Iyo, alongside Dogo Onsen and Hontani Onsen, with a history dating back to the Heian period. During the Edo period it served as a healing spa for the Imabari Domain, was redeveloped by the former Imabari clan in 1871, and the Nibukawa Onsen Cooperative was established in 1925. Modern road improvements in 1952 led to the development of today's hot spring resort. The water is a hypotonic alkaline cold mineral spring rich in radon, smooth and silky on the skin, long celebrated as a Bijin-no-Yu (Beauty Bath). Located within Okudogo Tamagawa Prefectural Natural Park, Nibukawa Onsen Hotel offers 28 guest rooms (including 5 rooms with private hot spring baths), a large public bath, open-air bath, family bath, and sauna, with picturesque views of Nibukawa Gorge through all four seasons.