Inuyama Castle is located on the southern side of the Kiso River in the sleepy town of Inuyama. The site of the castle was initially occupied by the Harigane Shrine, and the shrine was moved to Shirayamadaira so that the castle could be built on the steep hill. Inuyama Castle holds the distinct honor of being the oldest castle in Japan, though the date of its original construction a bit of a debate. The castle as it stands today was constructed in the year 1537 by Oda Nobuyasu, an uncle of the great warlord Oda Nobunaga. Inuyama Castle is only one of four castles in Japan designated as a National Treasure (Hikone, Himeji and Matsumoto Castles are the other three).