Iida Castle

About Iida Castle

Iida Castle is a hirayamajiro (a castle on a hill near flat ground) at the southern end of the Ina Valley in southern Nagano Prefecture. It was built on a terrace on the west bank of the Tenryū River and is a key strategic point of southern Shinano. Its history is said to have begun when the Banzai clan built it in the Muromachi period. In the Sengoku period it came under the control of Takeda Shingen and functioned as an important base for governing the Ina Valley. After the Honnō-ji Incident, Tokugawa Ieyasu took control of the Ina Valley, and throughout the Edo period Iida Castle developed as the center of politics and economy of the Iida Domain. Domain lords changed among the Ogasawara, Wakisaka, and Hori clans, which is also evidence that Iida remained a strategically important point for the shogunal family.

Geography and Culture of the Ina Valley

The Ina Valley, where Iida is located, is a long, narrow basin sandwiched between two mountain ranges of the 3,000-meter class, the South Alps and the Central Alps. Receiving the abundant waters of the Tenryū River, this valley had long seen agriculture and forestry develop. At the same time, it was an important transportation route connecting the Tōkaidō and Nakasendō with the Kōshū Kaidō. Samurai of the Ina Valley honed their martial arts in the harsh environment of the mountains and, as in other parts of Shinano, nurtured a sword culture that placed value on practicality. Iida is also known as the "Land of Apples," and fruit cultivation such as apples and pears, which developed after the Meiji era, added a new chapter to the agricultural culture of the Ina Valley.

The Takeda Clan and the Ina Valley

In the era when Takeda Shingen placed the Ina Valley under his control, Iida Castle functioned as an important base on the route of advance from Kai into Tōtōmi and Mikawa. Shingen governed by placing castellans in various parts of Shinano. In the control of the Ina Valley too, Iida Castle was always regarded as a strategic key point connecting Kai and Mikawa. After the fall of the Takeda family in the 10th year of Tenshō (1582), Iida Castle survived the turbulent final years of the Sengoku period, with its castellans changing many times as the forces of Oda, Tokugawa, and Toyotomi intersected. The changes of castellan during this period speak to the high strategic value of the Ina Valley itself. The samurai cultures each castellan brought in overlapped and formed Iida's historical depth.

The Ruins of Iida Castle and the Modern Era

Today, Osahime Shrine stands on the site of Iida Castle's honmaru, and the Iida City Museum stands on the site of the ninomaru. Part of the honmaru's stone walls, dry moats, and earthen ramparts remain. The Sakuramaru Gate (Akamon), which was the front gate of Sakuramaru, is the only building of Iida Castle that remains at its original location, and it conveys the style of that era to the present day. The Meoto-zakura ("husband-and-wife cherry") that remains at the site of the Sakuramaru palace is known as a cherry tree with an estimated age of about 400 years, in which the roots of a weeping cherry and an Edo-higan have joined. It has become a seasonal feature of spring at Iida Castle. The Iida City Museum also holds materials related to Iida Castle and is an important facility for learning the history of the Ina Valley.

Standing against the backdrop of the mountain ranges of southern Shinano, the Iida Castle ruins continue to give quiet emotion to visitors as a concentrated point of southern Shinano's history, where the legacies of Takeda and Tokugawa overlap.