Unazuki Onsen, located in Kurobe City, Toyama Prefecture, is a hot spring resort that opened on November 22, 1923, at the gateway to the Kurobe Gorge. It boasts the largest scale in Toyama Prefecture with a capacity of 3,500 guests. The hot spring water is drawn from Kuronagi Onsen about 7km upstream, a feat accomplished by industrialist Yutaka Yamada using pipes carved from pine wood. The water quality is weakly alkaline simple thermal spring with an exceptionally high source temperature of 87.8-98 degrees Celsius and an abundant daily flow of approximately 3,000 tons. The colorless, transparent water, said to have the highest transparency in Japan, is known as 'Tsubetube Bihada-yu' (silky smooth skin water), featuring four characteristics: ionic moisturizing effect, gentle weak alkalinity, detox effect from carbonic acid, and relaxation effect from minerals. Following the 2024 Noto Peninsula earthquake, the metasilicic acid content increased, enhancing its beautifying effects. Famous as the departure point for the Kurobe Gorge Railway trolley train, it attracts many tourists during the autumn foliage season. The hot spring town features the public bath 'Yumedokoro Unazuki' and multiple foot baths, enjoyable for both day trips and overnight stays.