Niida Fortress Remains:
Minamisanriku Town, Miyagi Prefecture.
A Medieval mountain fortress is discovered.

The Niida Fortress Remains comprise a Medieval mountain fortress located on a hill of 67 m elevation overlooking the Shizugawa bay in the town of Minamisanriku, in the northeast portion of Miyagi prefecture. An investigation was conducted prior to a core area development project following the tsunami. This mountain fortress is not seen in the documentary record, and its date of construction and lord are unclear. However, as this region was under the control of the Kasai family from the twelfth through the sixteenth centuries, it is thought that a military leader with relations to the Kasai family was its lord.

Defensive character becomes evident

In the current investigation there were six yards (level areas), six moats, and eight earth embankments ascertained, and on the level areas multiple buildings and rows of pillars were found. Artifacts that were recovered include stoneware, old coins, whetstones, stone bowls, tuyeres (bellows nozzles), and slag. There were large-scale embedded-pillar buildings in Yards 1 and 2, which are seen to have been the principal parts of the fortress. The moats were up to 8 m wide and 3 m deep, and parallel with the moats were embankments encircling Yards 1 and 2. The difference in height between the tops of the embankments and the bottoms of the moats reached 5 m, and these two features were mutually linked to serve for the function of defense.

A valuable case of investigating a mountain fortress in its entirety

From the recovered artifacts it appears that construction dates to the first half of the fifteenth century (Muromachi period), with abandonment by the seventeenth century (Edo period). Examples such as this of a mountain fortress being investigated in its entirety are rare nationwide, and this has become a valuable investigation for understanding mountain fortresses in the surrounding region. (Sasaki Masaru)

Panoramic view of the Niida Fortress Remains (from the north)

Shizugawa bay is visible in the distance. Remains of mountain fortresses dot the vicinity, including those of the Ronzan and Kiyara fortresses to the east, and the Komori, Asahi, and Hanayōgai fortresses to the west.

Plan of the Niida Fortress Remains
Adapted from Hakkutsu sareta Nihon rettō 2014 [Excavations in the Japanese Archipelago, 2014](Bunkachō [Agency for Cultural Affairs], ed., Asahi Shimbun Publications, 2014).