Kii Castle
was a castle structure between Miyaki District, Saga and Chikushino, Fukuoka, Japan. Kii Castle has been designated as being of special national significance.

History
Kii castle was built by Yamato court. Following the defeat of Yamato Japan in the 663 battle of Hakusukinoe by an alliance of Tang China and the Korean kingdom of Silla, Emperor Tenji ordered the construction of defenses against a possible invasion.

Kii Castle was listed as one of　the Continued Top 100 Japanese Castles in 2017.