There were many battles of Ypres, with the first taking place between October 19 – November 22nd, 1914, in which the French, Belgium, and British Expeditionary Force (BEF) armies fought the invading Germans.
The battles that represent the First Battle of Ypres include the Battle of Langemarck, Battle of Gheluvelt, and the Battle of Nonne Bosschen.
The Second Battle of Ypres was fought from April 22nd – May 25th, 1915. This included the infamous use of chlorine gas between Langemark and Gravenstafel.
The Battle of Passchendaele was the Third Battle of Ypres, the Battle of the Lys was the Fourth Battle of Ypres, and finally, the Fifth Battle of Ypres was September 28th – October 2, 1918.