Battle of Étreux
1914 CE.
Shown on the map at 49.995°, 3.658°.
The Rearguard Affair of Étreux was fought at Étreux by the British Expeditionary Force during the Great Retreat on the Western Front in 1914.
Text from the Wikipedia article Rearguard Affair of Étreux, licensed CC BY-SA 4.0.