Hyotan Onsen

Hyotan Onsen is a historic day-trip hot-spring complex founded in 1922 in the Kannawa district of Beppu, Oita, the area with the greatest volume of hot-spring water in Japan. It is the only onsen facility to hold three stars in the Michelin Green Guide Japan.

Hot-spring water & source

The spring is a sodium-chloride hot spring (hypotonic, weakly acidic, high-temperature) with a pH of about 3.1. The source gushes at roughly 100.4°C, and the water is served at 100% free-flowing strength (gensen towari kake-nagashi). Rather than diluting it, the facility cools the water with its proprietary "Yumetake" bamboo cooling system to preserve the full mineral content.

Baths

• Indoor baths: a large public bath including the signature gourd-shaped (hyotan) tub, plus a drinking fountain and a steam-inhaling station.
• Outdoor baths: open-air rotenburo set in a green garden setting.
• Waterfall baths (utase-yu): cascading streams of hot spring water that massage the shoulders and neck.
• Sand bath (suna-yu): guests are buried in naturally heated sand warmed by Beppu's geothermal heat, for detox and relaxation.
• Steam bath (mushi-yu): a hot vapor bath using the site's natural steam.
• Family baths: private rental baths available by reservation.
• Foot bath (ashi-yu): a complimentary footbath of pure spring water near the entrance.

Setting

The complex sits at the entrance of Kannawa's steam-wreathed onsen street, about 700m east of the Kannawa bus station, roughly 10 minutes by car from Beppu IC.