Suwa-taisha Shrine, which consists of four shrines located to the south and north of Lake Suwa-ko, is one of the oldest shrines in Japan, and has more than 10,000 branches across the country. The shrine was admired by many notable warlords, such as Takeda Shingen and Tokugawa Ieyasu. Its Onbashira-matsuri Festival is a traditional event during which a huge fir tree (measuring 1 meter in diameter, 17 meters in length, and weighing 12 tons) is cut down on the mountain and people drag it into the town to set it up within the shrine grounds.