It is thought that Hamagawajō was built by the Nagano Clan as one of the satellite fortifications of their main base of Minowajō, and manned by one of their vassals, Fujii Tomotada. The castle, which had a perimeter of 150m at its longest point, and moats 10m in width on three sides (in the north a branch of the Ino River was used as a moat), played a frontline defensive role in the Battle of Wakadahara. Nagano Narimori lost that battle to the forces of Takeda Shingen, and retreated to Minowajō to rally his forces, at which time Hamagawajō was likely occupied by the invaders.
The remains of Hamagawajō consist of a corner segment of dorui (earthen ramparts) and karabori (dry moats). The site is now fields and housing plots, and an explanatory board can be found on the roadside in what was once the fort’s outer bailey. A path leads from the road by the sign to the earthwork ruins. Be mindful that much of the site is now used as farmland and is private property.
|English Name||Hamagawa Castle|
|Founder||Nagano Clan; Fujii Tomotada|
|Year Founded||Sengoku Period|
|Castle Condition||Ruins only|
|Historical Period||Pre Edo Period|
|Access||Ino Station on the Jōetsu Line; 60 minute walk.|
|Visitor Information||24/7, Free; Fields|
|Time Required||15 minutes|
|Location||Takasaki, Gunma Prefecture|
|Coordinates||36° 22' 19.16" N, 138° 58' 51.10" E|
|Added to Jcastle||2022|
|Admin Year Visited||Viewer Contributed|
|Friends of JCastle|