Tsubakijō was constructed by Ueno Morinaga in the late 12th century. Morinaga was the seventh son of Ogasawara Nagatsune, but took the name Ueno after receiving a fief in the area of that name. In the Nanbokuchō period (14th century), Takeda Nobuaki, the son of Takeda Nobutake, took over Ôi Manor, as it was known, and became Lord Ôi Nobuaki. During the Sengoku period, Lord Ôi Nobutatsu and his son, Nobukane, repelled an attack on Tsubakijō by Takeda Nobutora in 1513. By 1520 the clan was reconciled to Nobutora, and Nobutatsu’s daughter, Zuiun’in (later nunnery name), married him; she would give birth to Takeda Harunobu who would later become known as Takeda Shingen.
Tsubakijō was an earthworks castle with a main, secondary and tertiary bailey. Baileys were divided by karabori (dry moats) and dorui (earthen ramparts), forming angular but irregular layouts. The third bailey was subdivided into smaller compounds ensconced by dorui. The main bailey had both karabori and dorui to protect it. Ground-penetrating radar scans have revealed the remains of yakkenbori type moats; these are a type of moat ‘V’-shaped in configuration, rather than flat-bedded, which are very steep and difficult to traverse. Yakkenbori are often karabori built when water-filled moats would be impractical.
Tsubakijō (‘Camellia Castle’) is known as the castle of Takeda Shingen’s mother. Located in the historical Koma County, it is also called Uenojō, though this is not to be confused with (the commonly known as) Kai Ueno Castle in Yatsushiro County. This earthworks fort was constructed in an area located on plateau with several wooded ravines looming over the Kai Basin like a giant comb. The creeks are like the fingers of a comb. So perhaps that is why an area below is called Kushigata? To me, viewing it from above at Nakano Castle (Kai), the plateau looked like a giant hand or paw had descended from the Southern Alps.
Few ruins remain of Tsubakijō, though some piled earth in the field north of Honjūji temple represents the remains of the castle’s main bailey. The graves of the Ôi Clan are located by the road at the corner of the temple where there is also an explanation board for the castle, and the graves of the Akiyama Clan can be found in the field with the camellia tree. To the south of the castle precincts there is ishigaki (stone-piled retaining walls), but these are Edo period at the oldest, piled for the temple not the castle. Nonetheless, they represent the castle’s southern boundary’s defensive line. There is a marker for the castle at the entrance to the temple.
|English Name||Tsubaki Castle|
|Founder||Ueno Morinaga; Ôi Nobuaki|
|Year Founded||12th Century; 14th Century|
|Castle Condition||Ruins only|
|Historical Period||Pre Edo Period|
|Access||Ichikawa-Daimon Station on the Minobu Line is the nearest station.|
|Visitor Information||24/7 free; temple|
|Time Required||30 minutes|
|Location||Minami-Alps, Yamanashi Prefecture|
|Coordinates||35° 36' 10.30" N, 138° 26' 31.60" E|
|Added to Jcastle||2023|
|Admin Year Visited||Viewer Contributed|
|Friends of JCastle|
|Oshiro Tabi Nikki|