The National Redoubt (, ) was a strategic defensive belt of fortifications built in Belgium. The National redoubt was the infrastructural cornerstone of Belgian defensive strategy from 1890–1940. The following fortifications and defensive constructions were an integral part of the National redoubt: the Fortified Position of Liège (Luik) with a number of forts the Fortified Position of Namur (Namen) with a number of forts Fort Eben-Emael the K-W line: a "canal" from Koningshooikt to Wavre, to defend against tank incursions another anti-tank canal in the Kempen, roughly aligned with the outer ring of fortifications around Antwerpen the coastal defenses as a retreat position against invasion troops The most important part of the national redoubt was a double ring of defensive forts around the city and port of Antwerp. The National Redoubt was a -long belt of fortifications built from 1859 to 1914, as the strongest defensive position of Belgium in case of invasion. Background Until the autonomy of Belgium in 1830 the defence of Antwerp consisted of the citadel and the Spanish city walls near the current De Leien (Italiëlei, Frankrijklei, Britselei, Amerikalei) bounded on the south by the Zuidkasteel (just north of the current Palace of Justice) and bounded on the north side by the Noorderfort, around the area of the current Kattendijkdok. The forts Liefkenshoek, De Perel, St. Marie and St. Philip were built during the Eighty Years War in 1584 by the Duke of Parma (Alexander Farnese) to block the supply of (the Hollanders in) Antwerp. These forts were in the bend of the river Scheldt in Kallo. Independent Belgium From 1830 to the mid-19th century, the defence of Belgium consisted of twenty fortified cities (called the Wellington Barrier), which were to form a defence against France. The defence of Antwerp was also aimed at the river Scheldt. This function was fulfilled by the forts De Perel, Burcht, Isabella and Saint Marie. The Scheldt defence was complemented by the development of the Vlaams Hoofd Fort, west of the current terminus of the St. Anna Tunnel. Act of 1851 Halfway through the 19th century after the emergence of Napoleon III in 1851, it was clear that the Belgian army did not have the capability to resist an attack from France. It was necessary to centralise defences and so a ring of fortresses around Antwerp, forten 1-7, were originally built as earthen ramparts but later reinforced by stone structures.