Original WW1 British Army map of the YPRES SALIENT recording changes to the frontline following the Germans’ LYS OFFENSIVE (4th Battle of YPRES) - also known as the "BATTLE OF THE LYS". The survey date (24th May 1918) shows that this second phase of the German Spring Offensive had already stalled three weeks earlier, but this is a map which reveals Allied concerns that the Ypres Salient may reignite resulting in further losses along this pivotal sector.
