Hayashi castle was a 15th-century castle, (alternatvley known as Hayashi-jo, Fukuyama-jo) in Satoyamabe Matsumoto city, Nagano, Japan. A mountain-type castle, it is now largely ruins. The site is sometimes regarded as one castle, or two castles, Hayashikojo (the small castle) and Hayashiohjo (the larger castle).It is located in the southeastern par tof Matsumoto city.