Yunoyama Onsenkan is a day-trip bathing facility in the Yuki-cho area of Saeki Ward, Hiroshima City, Hiroshima Prefecture. The hot spring is said to have first erupted from crevices in the mountainside approximately 1,200 years ago. During the Edo period, in 1750 (Kan'en 3), the feudal lord Asano Yoshinaga of the Hiroshima Domain developed the site as an official therapeutic bathing retreat. The historic bathhouse, spring basins, and Yunoyama Myojin Shrine from that era have been designated as a National Important Tangible Folk Cultural Property, preserving the bathing culture of centuries past.

The spring water is classified as simple weak radioactive hot spring containing radon, and is colorless, transparent, tasteless, and odorless. The source temperature is approximately 23.5 degrees Celsius, a cold mineral spring, so the indoor bath is heated to around 41 degrees Celsius. The signature waterfall bath (utaseyu), however, uses unheated source water directly, and the cold stimulation is reputed to be effective for stiff shoulders and neuralgia. Therapeutic benefits include relief from rheumatoid arthritis, poor circulation, mild hypertension, gout, and chronic conditions.

The facility's most distinctive feature is its waterfall bath cascading from a rock face approximately 4 meters above ground. This source-fed waterfall bath is rare even in the Chugoku region and is so popular that some people have relocated to the area specifically for its therapeutic benefits. The facility offers gender-separated indoor baths, free coin lockers, and complimentary shampoo and amenities. Day-trip bathing costs 450 yen for adults and 150 yen for children. Summer hours (June to September) are 9:00 to 21:00, while winter hours (October to May) are 9:00 to 20:00.