Zenk?-ji is a Buddhist temple located in Nagano, Japan. The temple was built in the 7th century. Nagano City, established in 1897, was originally a town built around the temple. Historically, the Zenk?-ji is perhaps most famous for its involvement in the battles between Uesugi Kenshin and Takeda Shingen in the 16th century, when it served as one of Kenshin's bases of operations. Currently, the Zenk?-ji is one of the last few remaining pilgrimage sites in Japan.