The Onjo-ji Temple, as head temple of the Tendaijimon Buddhist sect, has long been considered as one of the Four Great Temples of Japan. Throughout history, the emperors Tenji, Kobun and Tenmu modified its structure and name through various imperial orders. Prince Otomo Yota no O, son of emperor Kobun, first started the building process of this huge and expensive structure, followed by emperor Tenmu who named it Nagarayama Onjo-ji. Its common name “Mii-dera” (“temple of the three wells”) comes from the miraculous spring in which the three emperors Tenji, Tenmu and Jito were given their firth bath (Ubuyu). Later, the great Buddhist teacher Chisho used this spring water to perform the Sanbu Kanjo ritual (Buddhist rite of passage during which the master figuratively “pours” his knowledge onto his student).