Mizubanjō was built around 1460 by the Ogasawara Clan as part of a network of fortifications surrounding their new headquarters at Hayashijō. Indeed Mizubanjō can be considered a branch fortification of Hayashijō, built to protect its rear from any possible assault coming from the valley or mountain passes beyond, and to protect the Ogasawara's water supply. An alternate name for the castle is Suibanjō (the character for "water" can be read either way).
Mizubanjō follows the ridge of a mountainous spur. Following the trail head which surmounts the mountain - the most difficult part of most yamajiro ruin ascents - there is a long, flat area with a small shrine. This is the start of Mizubanjō. Passing a horikiri one comes to a fork in the ridgeline. To the right is a feature called the 大手筋, the meaning of which I would translate if I was more sure of. From here two tatebori (climbing trenches) run down the mountain. This projection doesn't go anywhere so I carried on to the left. I came to a nijūhorikiri (double trench system). This is very clearly taller on one side than the other. Probably a wooden bridge used to stand here, one which could be retracted or demolished if the need arose. Now a path climbs up the trench, leading to a sub-bailey beneath the shukuruwa (main bailey). The shukuruwa is lined with both dorui (earthen embankments), now deformed, and ishizumi (stone-pilings), now collapsed apart from one segment at the back of the bailey which has held together somewhat. Protecting the rear of the shukuruwa is an extensive unejōtatebori network. How to describe this feature? It's as if a giant comb had been raked down each side of the mountain ridge creating climbing trench after climbing trench. Many of the trenches form into one single larger tench to continue on their journey down the mountain, like streams forming a river. The impression in the earth is most clear on the right as one comes down from the main bailey, although it's difficult to photograph.
|English Name||Mizuban Castle|
|Castle Condition||Ruins only|
|Historical Period||Pre Edo Period|
|Features||trenches, stone walls|
|Access||Matsumoto Station; taxi or bicycle|
|Visitor Information||24/7 free|
|Time Required||60 mins|
|Location||Matsumoto, Nagano Prefecture|
|Coordinates||36° 13' 27.23" N, 138° 1' 11.42" E|
|Year Visited||Viewer Contributed|
|Added to Jcastle||2020|