Imai Fort




Built along a long river terrace, Imai-toride was likely a satellite fortification of Takei Castle used to protect the fertile plain. Of details little is known.

Visit Notes

This site went under my radar for a long time, despite being close enough for me to cycle there after work – which is what I did. Unfortunately the ruins of this earthworks fort have been obliterated in recent times and the site now hosts a solar panel array. It may be a small site in the middle of nowhere, but did its history mean nothing to locals? The site relatively recently had the ruins of kuruwa (baileys), dorui (earthen ramparts) and tatebori (climbing trenches). The land is currently off limits but I went virtually around the whole thing, which was not simple because Imai-toride is a clifftop fort site. There is a natural creek hemming the site in to the north, which made for a natural defensive line, and I was able to enter here without going near the solar farm. From here I made my way along the steep terrain which separates the upper plain from the river plain below. Most of this area has been built over with a large, modern retaining wall. In one place I found what looked like a deformed tatebori but that and deformed baileys are about it. A large pylon also sits next to the site. Pylons converge here because the site’s neighbour is the Shin-Shinano Frequency Converter Plant. The fort site, located on the border of the municipalities of Matsumoto (styled “City”) and Asahi (styled “Village”) is largely rural, but the huge power converter station located to the northwest is one of three plants in the nation used to convert the east’s and west’s different hertz (Hz) frequencies, since one half of the country runs on 60Hz and the other on 50Hz. It’s weird how the country is split in half like that, Japan being only one of a handful of countries which uses different frequencies; on a world map of Hz it could be fairly split in half! Anyway, I tried hard to find something of the medieval fort but there’s very little left, so that’s a shame. Many smaller historical fortification sites have little to no protection, so occasionally they are developed over and destroyed, especially if they’re not located on mountains. This is part of the reason why I’m keen to make a record of such sites, along with rustic architecture, in case they disappear.

  • Bailey turned into solar array

Castle Profile
English Name Imai Fort
Japanese Name 今井砦
Founder Mimura Clan
Year Founded Sengoku Period
Castle Type Hilltop
Castle Condition Ruins only
Historical Period Pre Edo Period
Artifacts Tatebori, Kuruwa
Features trenches
Visitor Information
Access Nearest station is Shiojiri Station on the Shinonoi and Chūō lines; 20 minute drive or 100 minute walk
Visitor Information Private Property
Time Required 30 minutes
Location Matsumoto, Nagano Prefecture
Coordinates 36° 8' 15.40" N, 137° 53' 20.44" E
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Added to Jcastle 2021
Contributor ART
Admin Year Visited Viewer Contributed
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