Fifth Battle of Ypres
1918 CE.
Shown on the map at 50.900°, 3.021°.
The Fifth Battle of Ypres, also called the Advance in Flanders and the Battle of the Peaks of Flanders (French: Bataille des Crêtes de Flandres) is an informal name of First World War battles in northern France and southern Belgium (Flanders) from late September to October 1918.
Text from the Wikipedia article Fifth Battle of Ypres, licensed CC BY-SA 4.0.