Built in: late 15th century.
Nirayama Castle is a hilltop castle located in Izunokuni, Shizuoka Prefecture. It was a very important castle for Hojo clan to protect Odawara. There is no exact record who and when this castle was constructed. In 1590, When Toyotomi Hideyoshi attacked Odawara castle, he attacked this castle with 50,000 soldiers. However, Samurai of Hojo kept this castle for about 100 days with only 3,600 soldiers. Later, Tokugawa Ieyasu negotiated and they gave this castle to Toyotomi Hideyoshi.
The main belly is located on the top of 42m tall hill. There are 4 different bellies and all of them are remaining in great condition. From the main belly, it has a great view of Mt. Fuji and Suruga Bay area.