Langemark is a village in the Belgian province of West Flanders, and a subdivision of the municipality of Langemark-Poelkapelle. The village has about 5,000 inhabitants. Besides the village center, there are also three smaller hamlets on the territory, Madonna, Bikschote and Saint-Julien/Sint-Juliaan.
Written as Langemarck on French, British and German maps, the village is known in military history as the scene of the first gas attacks by the German army in the western front, which marked the beginning of the Second Battle of Ypres in April 1915.
Wikipedia https://en.wikipedia.org/wiki/Langemark
Coordinates 50°54'48.737" N 2°55'6.122" E