Nasu’s Hot Springs
The history of Nasu’s hot springs (onsen) stretches back for more than a millennium. Mentioned in written records as early as the eighth century, Nasu grew in popularity as a hot spring resort such that by late in the Edo period (1603–1867), the “Seven Springs of Nasu” were ranked among the best in eastern Japan. Nasu continues to thrive as a hot spring destination. The waters of each onsen differ both in mineral composition and the benefits they are said to offer.
Nasu Yumoto Onsen
This is the oldest onsen source in the area: Shika no Yu, or “Deer Hot Spring.” Although the earliest documentation dates to 738, legend has it this onsen was discovered in 630 by a hunter who was chasing a wounded mystical white deer through the forest. He caught up with the deer to find it soothing its wound in the hot spring. Shika no Yu is a sulfuric spring that is 76ºC at its source point. The water is said to alleviate diabetes, anxiety, fatigue, and hemorrhoids.
Ōmaru Onsen
Ōmaru Onsen was discovered in 1691. One of Nasu’s more remote springs, it is located midway up the eastern slope of Mt. Chausu. The spring is 60ºC and slightly alkaline. It is said to benefit those with gynecological and colon disorders.
Benten Onsen
Benten Onsen was discovered in 1840, when the Buddhist goddess Benzaiten (also called Benten) appeared in a local man’s dream and directed him to the source. The spring is slightly alkaline and 50ºC. Its water is believed effective for gastrointestinal disorders, anemia, and indigestion.
Kita Onsen
Kita Onsen was discovered in 1696. Some parts of the onsen facility date to the late Edo period (1603–1867). One of its many baths is an open-air tub (rotenburo) the size of a swimming pool, and another bath is surrounded by huge masks of the mythical tengu (long-nosed bird-men). The source is a simple thermal spring with a temperature of 54ºC, reputedly good for children’s diseases, rheumatism, and infertility.
Yahata Onsen
Yahata Onsen (currently closed) was discovered in 1890 in the early Meiji era (1868–1912). It is located near a mountain slope where 20,000 azaleas bloom between mid-May and early June. Its saline spring water is 65ºC, and it is said to help with nervous disorders, heart disease, and gastrointestinal disorders.
Ōruri Onsen
Originally reserved for mountain ascetics who used it for self-purification, Ōruri Onsen was discovered in 1860. It is a slightly acidic sulfuric onsen that is 35ºC and said to help skin disorders and chronic urinary disorders.
Santogoya Onsen
Santogoya Onsen is an acidic onsen discovered in 1142. Located on the western slope of Mt. Asahi at an elevation of 1,500 meters, it can only be reached by hiking 2 hours from the Nasu Ropeway station on Mt. Chausu’s summit. The hot spring, which is 90ºC at the source, is thought to help treat nervous disorders, ulcers, and skin disorders.
