Ushio Onsen is an ancient hot spring located in Daito Town, Unnan City, Shimane Prefecture, with a history stretching back approximately 1,300 years. It is recorded in the Izumo no Kuni Fudoki, compiled in 733 AD, which describes a hot spring existing in the river of Suga village. Known as the inner retreat of Matsue, the hot spring was visited by Matsudaira Fumai, the feudal lord of Matsue Domain, during the Edo period for therapeutic bathing. Ushioso is one of the few member inns of the Association to Preserve Japan''s Hidden Hot Springs in the Chugoku region, cherished by hot spring enthusiasts nationwide as a hidden gem of Oku-Izumo.

The spring quality is sodium sulfate-chloride hot spring (hypotonic mildly alkaline high-temperature spring) with a source temperature of 45.9 degrees Celsius. The water is remarkably transparent, so clear that the bottom of the bath is visible, and is effective for neuralgia, rheumatism, gout, burns, cuts, skin diseases, hypertension, and cold sensitivity. A new source was drilled in 2005 and put into use from 2006. The private bath offers pure free-flowing source water.

The highlight is the outdoor bath Hoju-no-Yu, constructed from massive natural stones. The approximately 800-year-old chinquapin tree spreading its branches over the bath creates a spectacular canopy, offering a truly unique bathing experience beneath its shade. The indoor and outdoor baths are connected by glass doors, and the men''s and women''s baths are swapped at night. Overnight stays start from 15,550 yen per person with two meals. Dining by the irori hearth is popular, featuring cuisine prepared with abundant local ingredients. Day-trip bathing is available for 1,000 yen for adults and 500 yen for children from 11:00 to 16:00.