The Maginot Line was a defensive zone that was built in the 1930s to defend France against the possibility of a German invasion. The zone consisted of underground tunnels, artillery, anti-tank obstacles, and many other defensive structures and stratagems to slow down invading Germans. The Maginot Line stretched for approximately 200 miles (322 kilometers) near the French-German border.

During World War II, when the Germans did invade France, the Germans bypassed the Maginot Line by storming through neutral Belgium. Thus, the Maginot Line had failed its one great test because it was too short. The Line was also rendered obsolete by the fact that it did not provide defense against the new, modern warfare that included aircraft.