This onsen is the one of Japan's oldest, with Dogo Onsen in Ehime Prefecture and Shirahama Onsen in Wakayama Prefecture. Many documents since the 8th century mention this onsen.
According to these documents, among the many visitors to Arima Onsen are Gyoki (ツ行ナ?テョツ), a charismatic Buddhist monk in the 7th century, and Ninsai (ツ仁ツ青シ), another monk in the 12th century. Ninsai was said to greatly admire Arima Onsen and helped develop it. Hideyoshi Toyotomi visited this onsen several times in the 16th century.
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