Gensen Komanoyuso

Gensen Komanoyuso is a day-use hot spring facility in the Nagoya district of Izunokuni, Shizuoka, tucked in behind the Hatake onsen area. It opened in July 1977 as Komanoyu Gensenso, closed in September 2017, and reopened on November 28, 2017 under its current name after the indoor bath and changing room were renovated.

The water is an alkaline simple spring (hypotonic, alkaline). The main No. 3 source comes out at 38.0 degrees Celsius with a pH of 9.2 at about 203 liters per minute, and together with source No. 1 the flow reaches about 280 liters per minute. The water is colorless, clear, and nearly tasteless and odorless. The baths are free-flowing (kakenagashi) with no added water and no recirculation, kept lukewarm at 36 to 41 degrees Celsius, and only some of the tubs in the men's indoor bath are heated.

The indoor area has several tubs at different temperatures plus a half-body bath. The separate men's and women's open-air baths run along a mountain stream with four tubs each, including hot and lukewarm tubs, a herbal bath that changes daily, and a waterfall-style spray bath that closes from December to March. Admission starts at 950 yen for 90 minutes. A log-cabin style rest room, a large lounge, a lunch-only restaurant, and private rest rooms are also available.