Located by the seashore in Waian Village, Penghu County, covering an area of 8 hectares, Xiyu Western Fort is also surrounded by solid walls in all directions and is the most complete and largest ancient fort in Penghu. In Sino-French War, Penghu was defeated by the solid boat and armament of France, so that the French army occupied Xiyu and Makung. "Xiyu Western Fort" was personally inscribed by Li Hong-Chang, so it is also called "Li Hong-Chang's Ancient Castle" and "Western Fort Castle". As the same as Xiyu Eastern Fort, it is also listed as a Class A heritage and is actively being maintained.