Sunaharai Hot Spring (Sunaharai Onsen) is a long-established ryokan in Iida City that has operated since the Edo period and is popular for day-trip bathing. It offers a variety of baths known as the Seven-Color Baths and features a natural alkaline simple hot spring. The sauna uses far-infrared heaters set at 80°C–90°C, providing solid heat for a good sweat. A 16°C cold plunge bath chilled by a chiller and an outdoor relaxation area where you can enjoy fresh air and greenery make it ideal for relieving travel fatigue.