Hirotajō was first built by the Hirota Clan in 1400 as a simple fortified residence. The Hirota were succeeded by the Fujimaki Clan who built their own residence immediately to the west. However, these initial medieval residences appear to have been abandoned before Takeda Shingen conquered the area. Takeda vassal Ôbinata Naonaga became castellan of Hirotajō from 1555 and expanded the fortifications into several rings of defences for use during the Kawanakajima campaigns.
The later expanded fort is sometimes distinguished as 'Hirota-toride'. The inner fort of Hirota-toride measured 54m east-west and 90m north-south. The outer fort ran 144m east-west and 164m north-south. Shōryūji was founded within the fort in 1577 by Ôbinata Naoie, Naonaga's son, as the earlier Jizō hall, probably built by the Hirota Clan, had fallen into disrepair by the time of the fort's construction, and Naonaga had lamented this. Shōryūji still stands today; its necropolis contains a cenotaph for Naonaga, and the temple hall bears the Ôbinata crest.
Hirotajō is a hirajiro (flatland castle) site in Tamaki village, Inasato Township, Nagano Municipality. No ruins remain, and the site is now a temple called Shōryūji. Coincidentally, the temple contains an original castle structure, a miyagura (watchtower) said to be a relocated tower from Matsushirojō where it was used as a sumi-yagura (corner turret). The miyagura is covered in sheet metal rather than wooden boards, but it is painted so it looks okay. The original materials can be seen when looking up at the crow's nest.
|English Name||Hirota Castle|
|Alternate Names||Hirota-toride (広田砦)|
|Founder||Hirota Clan; Ôbinata Naonaga|
|Year Founded||1400; 1555|
|Castle Condition||No main keep but other buildings|
|Historical Period||Pre Edo Period|
|Access||Imai Station on the Shin'etsu Main Line; 40 minute walk|
|Visitor Information||24/7 free; temple|
|Time Required||30 minutes|
|Location||Nagano, Nagano Prefecture|
|Coordinates||36° 35' 40.24" N, 138° 10' 24.67" E|
|Added to Jcastle||2023|
|Admin Year Visited||Viewer Contributed|