* Image is for illustrative purposes only.Iiyama Castle
飯山城
Iiyama Castle is a historic castle in Chūbu dating from the Muromachi to Edo Period, whose lord was Honma clan (Muromachi period) → Uesugi Kenshin (major reconstruction) → Sanada Nobuyuki (entered domain 1615).
Overview
Iiyama Castle (Iiyama-jō) is a mountain castle in Iiyama City, Nagano Prefecture, occupying a strategic position at the confluence of the Chikuma River (Chikuma-gawa) and a tributary. It is believed to have originated as a residence established by the Izumi clan during the Muromachi period. In the Sengoku period, Uesugi Kenshin undertook substantial renovation and expansion, making it a military strategic hub connecting Echigo (Niigata) and Shinano (Nagano). Kenshin frequently used this castle as a base for military operations into northern Shinano and it played an important role in the Kawanakajima battles (1553–1564) against Takeda Shingen. After the Battle of Sekigahara, Sanada Nobuyuki entered the domain in Genwa 1st year (1615), and thereafter served as the administrative seat of Iiyama Domain (20,000 koku) until the Meiji Restoration. Today it is maintained as Shiroyama Park, with the remains of stone walls and earthworks well-preserved. Designated as one of Japan's Next 100 Famous Castles, it is known as a historic site where one can experience the snow-country culture and Sengoku history of northern Shinano.
Connection to Swords
Iiyama Castle holds a special position in Japanese sword history as a castle associated with Uesugi Kenshin. Kenshin is known among Sengoku warlords as one of the foremost sword enthusiasts and collectors, and famous named blades such as the Kenshin Kagemitsu and the Sanchōmō remain renowned as swords possessed by Kenshin. In particular, the Sanchōmō (unsigned, Bizen Fukuoka Ichimonji school, Kamakura period) was purchased by Setouchi City, Okayama Prefecture, for approximately 500 million yen in 2019 and repatriated as a blade with Kenshin associations, gaining national attention. Iiyama Castle served as a base for Kenshin's rule of northern Shinano, and it is said that the swords carried by Kenshin when passing through or staying at this castle during expeditions such as the Kawanakajima campaigns were likewise fine examples of Echigo-made blades. Furthermore, Sanada Masayuki and Nobuyuki of the Sanada family were based in nearby Ueda and Matsushiro, and the culture of armor and weapons associated with the Sanada family was transmitted to northern Shinano.
Highlights
- Stone Walls and Earthworks of Shiroyama Park — historic site structures designated by Nagano Prefecture, stone fortifications preserving traces of both the Uesugi and Sanada families
- Military Headquarters of Uesugi Kenshin's Rule of North Shinano — strategic base of the Kawanakajima Campaign, a place where visitors can experience Kenshin's military advance routes
- A Place Connected to Sanada Nobuyuki — Iiyama Domain historical records conveying post-Sekigahara governance, the sword and armor culture of the Sanada family
- Views of the Chikuma River — the majestic landscape of the Chikuma River, the Northern Alps, and Iiyama city skyline as seen from the castle ruins
- Iiyama City Local History Museum (adjacent to castle ruins) — exhibits historical materials related to Iiyama Castle, Iiyama Domain, and Uesugi Kenshin
- Snow Country Culture of North Shinano — landscapes and traditional customs unique to heavy snowfall regions, also renowned as the birthplace of skiing
* Opening hours and admission fees are subject to change. Please check the official website before visiting.