When the Caesar C Line defenses, manned by the German Fourteenth Army, were breached by the US Fifth Army on 30 May 1944, following the breakout from Anzio, the road to Rome was finally opened. The Germans retreated to their next line of defence, the Trasimene Line where the Fourteenth Army re-aligned with the German Tenth Army before withdrawing to the formidable defences of the Gothic Line.