This is a secluded one-inn hot spring resort located in the mid-slope of South Hakkoda Mountains, near the entrance of Oirase Stream in Towada City, Aomori Prefecture. Historical documents indicate that a hot spring therapeutic lodge existed at this site as early as the Kyuan 3rd year (1147) during the Heian period, making it a secret hot spring with approximately one thousand years of history. Surrounded by the primeval beech forests known as Towada Jukai (Towada Tree Sea), it is situated in a nature-rich environment at an elevation of about 450 meters.

The most distinctive feature is the extremely rare "gensen-waki-nagashi" (source spring flowing) hot spring, which is uncommon even in Japan. Since the source spring is located directly beneath the building, fresh hot spring water that has not been exposed to air continuously bubbles up from the bottom boards of the bathtub. This foot-emerging type of hot spring is exceptionally rare nationwide, and the sight of hot spring bubbles rising through the gaps in the beech wood bathtub boards is a unique experience found only at Tsuta Onsen.

The main building, constructed in Taisho 7 (1918), is still used as the main entrance and guest rooms today, retaining the atmosphere of a traditional hot spring inn from the good old days. The hot spring was deeply loved by Omachi Keigetsu, a travel writer from the Meiji period, who famously named various spots along the Oirase Stream and introduced them nationwide. It has also recently gained attention as a hot spring beloved by professional wrestler Antonio Inoki.

The hot spring is selected as one of Japan's 100 Famous Hot Springs and features two large public baths, "Kyuan-no-Yu" and "Senkyou-no-Yu," as well as private baths. Kyuan-no-Yu operates on an alternating schedule for men and women, with waka poems composed by Omachi Keigetsu displayed in the bathing area. Senkyou-no-Yu features separate facilities for men and women with a spacious atmosphere, with the height from the bathtub to the beams reaching 12 meters at the highest point. Furthermore, in the 2020s, the first luxury detached cottages in Tohoku region, produced by Kei Matsuba, opened, offering special accommodation experiences with semi-open-air baths.

The inn is surrounded by a group of lakes and marshes called Tsuta Seven Marshes, with Tsuta Marsh located approximately 5 minutes on foot. During the autumn foliage season, it is nationally famous for the mystical scenery of the morning sun illuminating Tsuta Marsh, with crimson autumn leaves reflected on the lake surface. Access to Oirase Stream is about 20 minutes by car, making it an ideal base for touring Hakkoda Mountains and Lake Towada.