Yunose Onsen is a historic hot spring located in Toyooka-shimo, Kibichuo Town, Kaga District, Okayama Prefecture. It was first established in 1921 (Taisho 10), with the spring water naturally emerging from the riverbed of the Toyooka River. The inn is now managed by a second-generation female proprietor. Situated quietly along a mountain stream, the single-inn hot spring enjoys relatively easy access from Okayama City, attracting many regular visitors from urban areas. The area is also known as a firefly viewing spot during summer.

The spring quality is alkaline simple hot spring with an exceptionally high pH of 9.7. The source temperature is relatively low at 27.1 to 29 degrees Celsius, classified as a cold mineral spring, so the water is heated for bathing. However, the source water is delivered unfiltered directly to faucets and showers. The slightly cloudy water has a distinctively slippery texture and carries a faint sulfur aroma. It is renowned as a beauty spring for its excellent moisturizing properties, and bathers report lasting warmth even after leaving the bath. Therapeutic benefits include relief from neuralgia, muscle pain, joint pain, fatigue, poor circulation, and skin conditions.

Day-trip bathing is available for 700 yen per adult and 400 yen per child, from 9:00 to 19:00. The inn is closed on Tuesdays and Wednesdays unless they fall on national holidays. Overnight stays start from 9,500 yen per person with two meals, featuring local mountain cuisine such as wild boar and duck hot pot. An adjacent campground operates from April to November, offering activities including bird watching and stream fishing.