Shinyu Onsen Kurikoma-so is a secluded single-inn hot spring retreat nestled in a beech forest at approximately 600 meters elevation on the slopes of Mount Kurikoma in Kurihara City, Miyagi Prefecture. The spring was discovered in 1720 during the mid-Edo period and was named 'Shinyu' (New Spring) because it was found after the nearby Komanoyu hot spring. It is counted among the Kurikoma Goyou (Five Hot Springs of Kurikoma) alongside Nuruyu, Yukura, Yuhama, and Komanoyu, and has been known as the 'Phantom Spring' among them. The water is a sulfur-calcium sulfate spring (hydrogen sulfide type), classified as a low osmotic pressure, weakly acidic, low temperature spring. The source temperature is 31.6 degrees Celsius with pH 5.6, producing milky white water with a subtle sulfur aroma. The inn maintains 100% natural free-flowing source water and preserves the traditional Japanese hot spring cure culture. It is particularly renowned as a therapeutic spring for diabetes, and is also effective for arteriosclerosis, cuts, burns, chronic skin conditions, chronic gynecological conditions, and hypertension. Located at the trailhead of Mount Kurikoma's Urakake route, it has long provided rest for mountain pilgrims. The bathing facilities include an indoor bath, a cypress wood open-air bath, and a reservable private open-air bath. Dining features local mountain vegetables, wild mushrooms, and iwana char fish tempura bowls. The inn has 8 guest rooms equipped with television, partial internet access, and yukata robes.