Himeji Castle, is a hilltop Japanese castle complex located in Himeji, in Hyōgo Prefecture, Japan. Himeji Castle, also called Shirasagijo (White Heron Castle) due to its white outer walls, is the best preserved castle in all of Japan. It serves as a classic example of Japanese castle architecture, having been designated a national treasure in 1931. Incorporating both strategic design as well as a very conscious awareness of space, it functions as a military command, a center for political life, and as a monument to the glories of an earlier age. Himeji Castle's construction dates to 1333, when a fort was constructed on Himeyama hill by Akamatsu Norimura, the ruler of the ancient Harima Province.