Iimori Castle (Azumi)
Iimorijō was the base of the Iimori Clan, and likely constructed in the early-to-mid' 16th century in preparation for the invasion of Aźumi by Takeda Shingen. In 1556, Yamagata Masakage, a general of Takeda Shingen, conquered Iimorijō. The castellan at that time was Iimori Harumori. Upon seeing the enemy forces arrayed against him, he fled to Echigo. It was thereafter that Iimorijō got the nickname 'Ichiyasanjō'. Whilst most castles with that pet name, such as those built by Toyotomi Hideyoshi, are so called because they were constructed rapidly - 'Ichiya' meaning 'one night' - Iimorijō got it because it fell in a single night! This is surely an embarassing fate for a castle.
Unlike his unfortunate castle, Iimori Harumori was at least able to redeem himself, as the next winter saw him fighting back against Takeda forces near Hirakurajō. Yamagata Masakage killed him in a battle in the snow. Harumori fled to die another day, perhaps finding more favourable circumstances for an honourable demise. He is said to have said: "It is essential for a general to survive and live up to his name, no matter how much shame he may be exposed to in life."
Iimorijō is a yamajiro (mountaintop castle) ruin in Kamishiro Township, Hakuba Municipality. Ruins include kuruwa (baileys), horikiri (trenches), dorui (earthen ramparts) and koguchi (gate complex) remains.
The time I visited Iimorijō I had just escaped from hell mountain where I didn't see a single trail but did see a bear. The trail to Iimorijō is park-like and pine-flanked, and the slope is gentle, so that it soothed my soul to climb it (note: I came from the south, the opposite side from Iimori Station, which requires less climbing). There are also sign posts, including one pointing out a well site, though I'm not sure where I was supposed to look.
The layout of Iimorijō is simple, as it is made up from three integral baileys straddling the ridge in a row. The topmost main bailey has dorui remaining to the west, and a koguchi entrance. The second bailey is set below the first and the third, and has some residual dorui to the west, as well as a terraced sub-bailey there. The third bailey is quite interesting and has some nicely preserved dorui. The bailey is snug, and is said to have been used as a stable or a place to shelter horses, though it may have realistically been intended chiefly for tight defence of the ridge. The embankments on either side of the castle which sit above the ridge are quite tall, but the trenches are shallow, and it is said that this fort was not very strong.
|English Name||Iimori Castle (Azumi)|
|Alternate Names||Ichiyasanjō (一夜山城 )|
|Year Founded||Early 16th Century|
|Castle Condition||Ruins only|
|Historical Period||Pre Edo Period|
|Artifacts||Horikiri, Dorui, Kuruwa, &c.|
|Access||Iimori Station on the Ôito Line; 8 minute walk to trailhead|
|Visitor Information||24/7 free; mountain|
|Time Required||30 minutes|
|Location||Hakuba, Nagano Prefecture|
|Coordinates||36° 39' 57.31" N, 137° 50' 26.02" E|
|Added to Jcastle||2023|
|Admin Year Visited||Viewer Contributed|
|Friends of JCastle|