Fort de Flémalle is one of twelve massive concrete fortifications built around Liège between 1881 and 1884 according to General Henri Alexis Brialmont's designs. Located about 7 kilometres southwest of Liège's center, this quadrangular fort overlooks the Meuse valley and represents innovative 19th-century military architecture, being among the first significant structures built entirely of unreinforced concrete rather than masonry. Heavily bombarded during World War I and again in World War II, the fort has been preserved as a museum where visitors can explore authentic Belgian weapons, uniforms, and equipment. Guided tours provide access to most of the fort's interior, offering insights into the daily lives of soldiers during the world wars.