Battle of Ypres
The Ypres Salient was the site of five battles during World War I: The First Battle of Ypres (19 October – 22 November 1914), the Second Battle of Ypres (22 April – 15 May 1915), the Third Battle of Ypres, also known as the Battle of Passchendaele (31 July – 6 November 1917), the Fourth Battle of Ypres, also known as the Battle of the Lys (9–29 April 1918), and the Fifth Battle of Ypres (28 September – 2 October 1918).