This part of the infamous “Siegfried Line” is a well-preserved specimen of an engineering project so big, that civil engineers still scratch their heads at the sheer audacity of its scope.

Construction started in 1936 as an answer to the French Maginot Line and ran for 390 miles from the border with the Netherlands all the way south to the Swiss border. More than 18,000 bunkers, tunnels, tank traps and machine gun positions were meant to protect Germany’s western flank.

But after the start of World War 2 in September 1939 and the subsequent invasion of France by Germany in 1940, the line was mostly abandoned. However, years later after the invasion of Normandy by the Allies, the line was reconstituted with men and equipment. Many parts of the line never saw direct combat with notable exceptions in the Hürtgen Forest in August of 1944.

Many parts of the line were demolished after 1945, but some were preserved for historical purposes, including these bunkers in Bad Bergzabern.