Yado Yunosato is a member inn of the Association for the Preservation of Japan''s Secret Hot Springs, located in Musashi, Totsukawa Village, Yoshino District, Nara Prefecture. It belongs to the Yusenchi Onsen area within the Totsukawa Onsen-gou (hot spring village group). The history of Yusenchi Onsen dates back to the Muromachi period; a 1450 earthquake altered the underground hot spring veins, causing water to emerge in the village of Musashi. Historical records document a therapeutic bathing visit by Jitsuji, the youngest son of Rennyo (8th head priest of Hongan-ji Temple), in 1552, and a visit by the feudal lord Sakuma Nobumori in 1581. The temple Tosenji, which gave the onsen its name, is associated with the legendary ascetic En no Gyoja and the great Buddhist monk Kukai.

The spring water is classified as a simple sulfur spring (hydrogen sulfide type) with a pH of 7.6, a source temperature of 55.5 degrees Celsius, and a flow rate of 87 liters per minute. The water is colorless and transparent with a gentle sulfur scent, delivered as 100% free-flowing from the inn''s private source with no heating, dilution, or chlorine treatment. On June 28, 2004, the Totsukawa Onsen-gou became the first hot spring district in Japan to issue an official ''kakenagashi'' (free-flowing source water) declaration. The waters are known for benefits including chronic gynecological conditions, neuralgia, muscle pain, joint pain, and chronic skin conditions.

The inn features separate indoor and outdoor baths for men and women. A distinctive design channels water continuously overflowing from the indoor bath through the window frame into the open-air bath. The outdoor bath offers views of the Totsukawa river gorge, allowing guests to bathe while enjoying the natural beauty of each season.