Oyadani no Yu

Oyadani no Yu is a free wild open-air bath on the Jadani gorge, along the Hakusan-Shirakawago White Road in Chugu, Hakusan City, Ishikawa Prefecture. It sits directly opposite Ubagataki Falls, a 76-metre cascade listed among Japan's 100 finest waterfalls, and is regarded as one of the country's most spectacular natural baths. Once known locally as Dosu no Yu, the bath uses hot water rising from the bed of the Jadani River, channelled into a hollow worn naturally into the bedrock. Natural discharge ceased in 2012 and the bath closed, but a pump was installed in 2015 and it reopened in July 2017 after roughly five years.

The water now used for bathing comes from the Oyadani Onsen No. 1 source, recorded as a simple hot spring (hypotonic, neutral, high temperature) with a source temperature of 64.5C, a pH of 6.6 and a yield of 41.5 litres per minute drawn by pump. Some tourism materials instead describe the riverbed spring as a sodium bicarbonate-chloride water, so published descriptions of the mineral content differ. The water is colourless and clear, served straight from the source with no dilution, reheating, recirculation or chlorination. The hot source water is cooled naturally as it runs across the rock face, leaving the pool at around 39C, though on some days it is simply too hot to enter. The water has long been said to help skin complaints.

There is a single oval mixed-gender pool, plus a free foot bath beside the viewing platform for the falls. There is almost no enclosure and no proper changing room, so swimwear is compulsory. Bathing itself is free, but the White Road toll must be paid separately: 1,700 yen one way for an ordinary car and 1,400 yen for a light vehicle. Opening dates and hours follow the White Road itself, which is open from early June to 10 November, 7:00 to 18:00 in June to August and 8:00 to 17:00 in September to November. Note that rockfall around the bath in June 2025 closed the footpath down from Jadani Enchi, so Ubagataki Falls and Oyadani no Yu are out of use. As of July 2026 they remain closed with no reopening date announced, so check conditions with the Hakusan Rindo Ishikawa Management Office (076-256-7341) before visiting.