Westwall

Westwall, also known as Festung Westwall or the Siegfried Line, is the German defensive line constructed along the western border of Germany in the 1930s and early 1940s. Built by the regime of Adolf Hitler, the line extended roughly from the Swiss border in the south to the Belgian and Dutch borders in the west, following natural terrain such as the Rhine valley. The fortifications comprised thousands of concrete bunkers, pillboxes, artillery positions, minefields, anti-tank obstacles, and an extensive network of tunnels and command posts, many linked by underground passages. The Westwall was designed to slow an invading force, channel advances, and provide time for mobilization, air support, and coordination with neighboring sectors.

In World War II, the line served primarily as a static defense in 1939–1940 and later as a line to be penetrated rather than decisively held. German forces defended several sectors during the early campaigns, but the invasion of France in 1940 largely bypassed and outflanked the line. From 1944 to 1945 Allied advances through Western Europe breached or bypassed many fortifications; the Westwall's role diminished as German defense collapsed. After the war, most of the fortifications were dismantled or destroyed, and the landscape gradually reclaimed the sites.

Today, remnants remain as archaeological and historical sites. Many bunkers and trenches are accessible as open-air monuments or in private or municipal possession; some areas host museums or guided tours. The Westwall is commonly referred to in German historiography as Festung Westwall, while Allied usage more frequently refers to the Siegfried Line. The term Westwall underscores its origin as a late-Interwar border defense that shaped German planning for war in the West.