The British offensive at Cambrai aimed to capture the local logistical hub for the Hindenburg line. The Mark IV tank played a pivotal role in the planned attack because of the gentle local topography and lack of artillery damage this relatively quiet stretch of the front line had sustained. Over 400 units were present on the battlefield, serving to disperse the barbed wire defences littered across no man’s land using fused high explosive shells that reduced cratering. The operation relied on surprise for success so the tanks and artillery were concealed prior to the attack, and a new ‘predicted fire’ artillery bombardment was employed, which caught the Germans off guard. The British advanced quickly at first but began to lose a number of tanks, one in particular broke the bridge at Masnières, meaning cavalry could not advance. Many of the useful advanced positions taken were subsequently lost in German counterattacks.