Zenkō-ji (善光寺) 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, Zenkō-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.