The Battle of the Bulge (also known as Ardennenoffensive, Ardennes Counteroffensive, and Rundstedtoffensive, Von Rundstedt Offensive to the Germans) (16 December 1944 – 25 January 1945) was a major German offensive launched through the densely forested Ardennes mountain region of Wallonia in Belgium, and France and Luxembourg on the Western Front towards the end of World War II. The Wehrmacht's code name for the offensive was Unternehmen Wacht am Rhein ("Operation Watch on the Rhine"), after the German patriotic hymn Die Wacht am Rhein. The French name for the operation is Bataille des Ardennes.
en.wikipedia.org/wiki/Battle_of_the_Bulge