Haraigawa Onsen is a hidden day-trip hot spring located in Makigawa, Tsushima-cho, Uwajima City, Ehime Prefecture, known as one of the rare sulfur springs in Shikoku. Tucked deep in the mountains near the Ehime-Kochi prefectural border, the rustic log-cabin-style facility is surrounded by lush nature and a tranquil atmosphere. The water is classified as a simple sulfur cold mineral spring (pH approx. 8.9, source temperature approx. 16C) and is regarded as one of the finest hot springs in Shikoku. Bathers can enjoy the silky, source-flow waters whose sulfur content is said to leave the skin moisturized long after the bath. The bathhouse follows the traditional method of heating the water with firewood, and a faint scent of burning wood drifts through the bathing rooms. In addition to the public baths Sakura-yu and Ume-yu, three private family baths Sagiso-yu, Rindo-yu, and Momiji-yu are available, making it a beloved hidden gem for those seeking authentic Shikoku hot spring culture.