The Hindenburg Line - Ludendorff's Defence in Depth

1916, the Year of Battles, had strained Germany's resources everywhere but especially on the Western Front they needed to defend their captured territory against an ever growing number of Entente Forces. Erich Ludendorff decided to shorten the front line where possible and built a new "Defence In Depth" line: The Siegfried Line. This defensive network was supposed to grind the Entente forces down while freeing up more German resources.