A day-trip hot spring facility with spectacular ocean-view open-air baths, located in Sueyoshi, Hachijo-machi on Hachijojima Island, Tokyo. Situated approximately 300km south of central Tokyo on the southernmost island of the Izu island chain, the facility is built on an elevated platform about 94 meters above sea level. From the open-air bath, visitors can enjoy panoramic views of the vast Pacific Ocean, Koiwato-ga-Hana headland, and the Hachijojima Lighthouse, while on clear nights one can bathe under a spectacular starry sky. The spring water is an iodine-containing sodium chloride strong salt hot spring with a source temperature of 47.5°C and pH 7.0 (neutral). The rare iodine-rich water is said to be effective for rheumatoid arthritis, gastrointestinal disorders, mild hypertension, diabetes, asthma, hemorrhoids, autonomic nervous system instability, fatigue recovery, and poor circulation. The facility features indoor and outdoor baths, with the outdoor bath shaped like a gourd resembling the shape of Hachijojima Island. The men's and women's baths alternate between even and odd days, so visiting on two different days allows guests to enjoy both bathing areas. Shampoo, body soap, and hair dryers are provided, and the facility includes a rest area with massage chairs. Admission is an affordable 500 yen for adults.