Unpoji Temple in Enzan Kamihagihara, Koshu City, Yamanashi Prefecture is a temple of the Myoshinji school of the Rinzai sect. Its sango (the name of the mountain where the temple is located) is Sakeishizan. It is said that the temple was founded in 745. Legend has it that when the monk Gyoki was perform the ascetic practices in this mountain, a stone was struck by a thunder and it was split in two, from which the image of Juichimen Kannon (Kannon with eleven faces) appeared. Gyoki carved this image on the bark of a nearby tree and made it the principal object of worship.
The temple buildings were all reconstructed during the Warring States period (1493-1573) by Takeda Nobutora, the 18th head of the Takeda clan. The Hondo (main hall), Kuri (the priest’s quarters) and Shin (the reception room) are all designated as National Important Cultural Properties. Japans oldest Rising Sun flag and the Sun Tzu’s flag, or commonly known as the Furinkazan battle flag, and Suwa Jingoki flag (the flag on which the name of the war god Suwa Myojin is written) are preserved and displayed in the treasure house, which shows that the temple had a close connection with the Takeda clan. In the precinct is a 100-year-old cherry tree called “Mine-no-sakura (a cherry tree in the peak),” which produces bright pink flowers in spring.