On the morning of 20th November 1917, the British launched a major offensive along a 10 km front to the southwest of Cambrai. The aim was to break through the Hindenburg Line, a vast system of German fortifications. For the first time, the attack relied upon the massive use of tanks. The early spectacular British advance was followed by a violent counter-offensive. After a month of fighting, the Battle of Cambrai finished with neither victors nor vanquished.