The Yser (Dutch: IJzer, French: Yser) is a river that finds its origin in the north of France, enters Belgium and flows into the North Sea in the town Nieuwpoort.
The source of the Yser is in Broxeele, in the Nord département of northern France.
The Battle of the Yser secured the coastline of Belgium for the allies in the "Race to the Sea" in the first three months of World War I.
Belgium had been invaded by Germany and the remnants of the Belgian Army pushed into the far south west of the country, behind a 22 miles front on the Yser Canal as the Germans tried to reach the French Channel ports of Calais and Dunkerque.
The historical importance of the Battle of the Yser was not only the fact that the Germans did not manage to defeat the Belgian army, but also that through the horror of war, and through the experiences of ordinary foot soldiers, Flemish national consciousness started to grow in the then overwhelmingly Francophone Belgian society.