Yato Castle

Yato Castle - Credit: Wikimedia Commons

was a Heian period yamashiro-style Japanese castle located in the Ōizumi neighborhood of the city of Hokuto, Yamanashi prefecture, Japan. It was the primary fortress of the warlord Henmi Kiyomitsu, ancestor of the Takeda clan. The ruins have been protected as a National Historic Site since 1993. Read more on Wikipedia

type: military structure
date from: late Heian period

Source: en.wikipedia.org