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The fortified position of Liège (French: position fortifiée de Liège [PFL]) was established after the First World War by Belgium to block the traditional invasion corridor through Belgium between Germany and France. In the First World War the Belgian Army held up the Germans for a week at Liège, delaying the German invasion of France, caused Belgium to consider a similar defensive strategy. Belgium rebuilt the Liège fortifications and extended them onto the Pays de Herve (Herve plateau) closer to Germany, using the most advanced fortification technology available.