A secluded single inn nestled deep within approximately 3,000 tsubo (nearly 10,000 square meters) of mixed forest along the Tanohara River, about 5 minutes by car from the Kurokawa Onsen hot spring village in the Aso Kuju National Park area. At an elevation of approximately 700 meters, the inn is enveloped in the sounds of the river and birdsong. Its greatest feature is two privately owned spring sources: Yakushi no Yu (Simple Sulfur Spring, pH 4.0, 29.4 degrees Celsius) and Bihada no Yu (Sodium-Chloride/Bicarbonate/Sulfate Spring, pH 6.9, 70.4 degrees Celsius), both delivered as 100% free-flowing from the source. Yakushi no Yu has been known since ancient times as a medicinal spring, said to heal cuts and skin diseases, and to benefit gastroenteritis when consumed as drinking water. Bihada no Yu features a distinctively bluish transparent water renowned for its skin-beautifying effects. Guests can enjoy seven different bathing experiences including the mixed-gender outdoor bath Moyai no Yu, women-only outdoor bath Shiki no Yu, gender-separated indoor bath Yakushi no Yu, and three private baths (Rokushaku barrel bath, cypress bath, and cut-stone bath) available free of charge for overnight guests. All 16 guest rooms feature private stone baths or outdoor baths. The founder believed that the greatest charm of Sanga is untouched nature itself, planting trees and channeling streams to preserve the natural landscape. The inn also accepts the Kurokawa Onsen bath pass (1,500 yen for entry to 3 locations).