Located at the heart of Yumura Onsen town in Shin-Onsen Town, Mikata District, Hyogo Prefecture, Arayu is a natural hot spring source with over 1,170 years of history, said to have been discovered in 848 by Jikaku Daishi, the third chief priest of the Tendai sect. Arayu is a naturally gushing (not drilled) thermal spring with a source temperature of 98°C, producing 470 liters per minute. The entire Yumura Onsen area boasts 60 spring sources with a combined output of approximately 2,300 liters per minute. The water quality is sodium-bicarbonate, chloride, and sulfate spring (hypotonic, mildly alkaline high-temperature spring) with pH 7.58, colorless and transparent. Known as a 'beauty spring' with 192.5mg of metasilicic acid, it has numerous therapeutic indications including muscle pain, neuralgia, joint pain, cold sensitivity, chronic skin conditions, and arteriosclerosis. A popular attraction at Arayu is the 'yugaki experience,' where visitors can boil eggs, wild vegetables, and bamboo shoots using the 98°C hot spring water. Along the Haruki River, a free natural flowing footbath stretching about 20 meters is available. The area is nationally famous as the setting for the NHK drama 'Yumechiyo Nikki.' In winter, excess hot spring water flows into the river, creating a magical scene of steam rising from the water surface.