Built in the Sengoku Period, Yashirojō was the residence of the Yashiro Clan, a branch clan of the locally powerful Murakami Clan. In 1553, the Yashiro, along with the nearby Shiozaki Clan, sided with Takeda Shingen. Takeda's advances this far into Shinano triggered a long series of skirmishes fought on and around Kawanakajima. In 1559, Takeda ordered the Yashiro to occupy Arato Castle, located across the valley to the south (it has been reconstructed in the present day). It is thought that Yashirojō was abandoned around 1560 with the construction of more important forts in the area such as Kaiźujō and Naganumajō further to the north and close to Uesugi territory.
The ruins of Yashirojō are located on a small mountain overlooking the temple Manshōji. The mount gradually declines until it recedes into the northern plain. Earthworks, such as trenches and terraced pocket baileys, can be found right the way down the mount, starting from just above the plain. The main bailey is located at the very top. Features include karabori (dry moats), kuruwa (baileys), and dorui (earthen ramparts).
|English Name||Yashiro Castle|
|Year Founded||Sengoku Period|
|Castle Condition||Ruins only|
|Designations||Local Historic Site|
|Historical Period||Pre Edo Period|
|Artifacts||Kuruwa, Koshikuruwa, Dorui, Karabori, Horikiri|
|Access||Yashiro Station on the Shinano Railway; 10 minute walk|
|Visitor Information||Free; 24/7; Mountain|
|Time Required||60 minutes|
|Location||Chikuma, Nagano Prefecture|
|Coordinates||36° 31' 58.37" N, 138° 7' 50.48" E|
|Year Visited||Viewer Contributed|
|Added to Jcastle||2020|