Hindenburg Line

The Hindenburg Line was a vast system of defences in northeastern France during World War I. It was constructed by the Germans during the winter of 1916–17. The line stretched nearly 160 km (100 miles) from Lens near Arras to the Aisne River near Soissons.The decision to build the line was made by Generals Paul von Hindenburg and Erich Ludendorff during the final stages of the First Battle of the Somme. The Hindenburg Line was built across a salient in the German front, so that by withdrawing to these fortifications the German army was actually shortening their front. The total length of the front was reduced by 50 km (30 miles) and enabled the Germans to release 13 divisions for service in reserve.
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