The Anju Castle is a military fortress built during the Goguryeo kingdom, later rebuilt during Joseon era.
It is located in Anju City, South Phyongan Province, North Korea.
[1] The inner fort dates from the Goguryeo period; it has walls along the ridge of the Kadu range on the shore of the Chongchon River.
The largest of them is called the Chilsong Pond, "which was studded with seven tiny islets resembling the Great Bear [constellation].
"[1] The fort features north, south, east and west gates, each built on a stone foundation with an archway and a gatehouse.