Ametoyajō was used as part of a network of fortifications protecting the territory of Aida and guarding the mountain trail that led between valleys (in former times mountain ridges were a frequently used means of going to-and-fro'). Specifically Ametoyajō guarded two major routes. It is located close to Gohontōge, a pass through the mountains between Aida and Akashina via a mountain village called Oniochi which is now abandoned. Furthermore Ametoyajō aided in the protection of Aida-juku, a checkpoint town on the Zenkōji-kaidō, a highway running from the Nakasendō (from Shiojiri-juku between Kiso and Suwa) through the heart of Shinano. It seems that the mountainside was once inhabited, and so Ametoyajō may have also offered a redoubt for villagers if they came under attack.
The ruins of Ametoyajō consist of at least one principal bailey protected by horikiri (trenches cut into the ridge) on both sides. The complex of trenches to the mountainside rear are, in typical fashion, the most formidable. However, further along the ridge, and in the direction I came from, there are a series of flattened peaks which may have been used as auxiliary baileys. In truth it's hard to tell them apart from the natural form of the ridge, but a dobashi (earthen bridge) located between two of these pseudo-baileys is quite suggestive of their former fortification. It seems that many of the forts used to protect Aida were quite narrow in profile and sometimes poorly developed, and Ametoyajō is typical of this characteristic.
To reach this site take the ridge at the crossroads where there is a trail just to the right when coming from below. I saw a ladder here with a hook at the top. There used to be a bell hanging there. It was used to alert villagers to fire. People used to live here on the mountain? It's incredible to think.
|Pre Edo Period
|Nearest station is Akashina Station on the Shinonoi Line; hike from Nabeyamajou Fort site; or forestry road access from Aida
|24/7 free; mountain
|Matsumoto, Nagano Prefecture
|36° 21' 54.76" N, 137° 58' 48.00" E
|Added to Jcastle
|Admin Year Visited
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