Hotel Iya Onsen

A private cable car drops 170 metres to riverside baths of fizzy, body-temperature sulphur water — Shikoku's great onsen adventure, if you don't mind stairs and a winding road

Hotel Iya Onsen sits on a cliff in the Iya Valley, and its signature is a cable car that descends 170 metres at a 42-degree angle to two open-air baths beside the river. The water is an alkaline sulphur spring at about 38°C, free-flowing, silky and slightly fizzy, so guests happily soak for a long time — 'neither heated nor diluted… silky sulphur water', as one wrote. Japanese reviewers rate it highly: 4.64 across 564 reviews on one major site and 4.63 on another, with the baths scoring highest (4.74–4.79). They also like the views, the L'Occitane amenities and local food — amego trout, Iya soba and Awa beef. The drawbacks: the riverside water is too cool to enjoy fully in winter, the baths are open to day visitors until about 17:00, there's a wait of 10–15 minutes if you just miss the car, and summer brings horseflies. Rooms with their own bath use spring water pumped up, heated and recirculated, which loses the fizz and smell. There's no lift and a lot of stairs, the approach road is narrow and subject to roadworks closures, and several reviewers felt dinner wasn't worth the price or found some newer staff less polished. Bloggers paid about ¥39,000–40,000 per person with two meals in rooms with a private bath.