Nirayama Castle
This is a hilltop castle, now largely ruins, built by Hojo Soun in the Izu Province in 1493.
Originally, Soun had his main castle at Kokokuji Castle. After building Nirayama Castle, Soun made it his main castle. The castle was well fortified, with western style fortifications, and had supporting forts on four nearby hills. Garrisoned with 3600 men, it withstood a siege against it by 40,000 troops under the command of Oda Nobukatsu for 3 months, with the defenders only giving up when the main castle for the clan was lost.
After the surrender, Tokugawa Ieyasu's retainer Naito Nobunari moved into the castle, respectively holding 10,000 koku to its name. He however, then left it in 1601, at which time it became abandoned.
Presently, there are some rough ruins, mainly just landforms indicative of where the castle would have been.
Coordinates: 35°03′14″N 138°57′21″E / 35.0538°N 138.9557°E
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