The Battle of Cambrai (20 November - 3 December 1917) was a British campaign of World War I. Noted for the first successful use of tanks in a combined arms operation, the British attack demonstrated that the Hindenburg Line could be penetrated, while the German counter attack showed the value of new infantry tactics that would later be part of the Kaiserschlacht. Liddell Hart called the battle "one of the landmarks in the history of warfare, the dawn of a new epoch."B. H. Liddell Hart, History of the First World War, Pan Books, 1972: 337 Cambrai is a French town in the Nord département (Nord-Pas-de-Calais). In 1917 it was a key supply point for the German Siegfried Stellung (part of the Hindenburg Line) and the nearby Bourlon Ridge would be an excellent gain from which to threaten the German rear to the north.