It is thought that Aruga Castle was first built around 1220 by the Aruga Clan. In 1542 Takeda Shingen invaded Suwa and the Aruga Clan sided with him initially. However, in 1546 Aruga Yasutoki sided with Kiso Yoshimasa and was destroyed by Takeda Shingen. Arugajō was then placed in the hands of Hara Toratane. In 1549 the Chino Clan were entrusted with the castle. By this time it had been considerably fortified.
The ruins of Aruga Castle consist of four baileys climbing like a staircase up a mountain ridge to the fifth and final bailey, the shukuruwa (main bailey). The main and second bailey are separated by a deep trench and a multilayered trench system also extends beyond the shukuruwa, protecting it in the rear where it was most vulnerable. The main and second baileys are also surrounded by dorui (earth-piled) ramparts. The dorui at the rear of the shukuruwa is the largest and most impressive segement of all the earthworks, and it looms over a karabori (dry moat). Beneath the climbing stairway of baileys a yokobori (lateral trench) runs, and a tatebori (vertical trench) protects the exposed lower reaches of the shukuruwa. And so Arugajō has lots of the features typically associated with yamajiro (mountaintop castles), most of which were formed primarily from earthworks and making deft use of natural terrain. The start of the trail which leads to the castle site is marked by a reconstructed kabukimon (a type of simple gateway).
|English Name||Aruga Castle|
|Castle Condition||Ruins only|
|Historical Period||Pre Edo Period|
|Artifacts||Hori, Kuruwa, Koshikuruwa, Dorui, Yokobori, Tatebori, reconstructed kabukimon|
|Access||Kami-Suwa Station on the Chuo Line; 70 minute walk|
|Visitor Information||24/7 free; mountain|
|Time Required||One Hour|
|Location||Suwa, Nagano Prefecture|
|Coordinates||36° 1' 2.35" N, 138° 4' 51.02" E|
|Year Visited||Viewer Contributed|
|Added to Jcastle||2020|