Hakusan Castle

Hakusan Castle - Credit: Wikimedia Commons

was a Heian period yamashiro-style Japanese castle located in the Kamiyamamachi neighborhood of the city of Nirasaki, Yamanashi prefecture. It was the primary fortress of the warlord Takeda Nobuyoshi, the ancestor of the Takeda clan. The ruins have been protected as a National Historic Site since 2001. The castle is also known as Read more on Wikipedia

type: military structure
date from: late Heian period

Source: en.wikipedia.org