Battle of the Segre
1938 CE.
Shown on the map at 41.617°, 1.000°.
The Battle of the Segre is the collective name of a series of battles that took place along the Segre River between 4 April 1938 and 3 January 1939 during the Spanish Civil War, after the Nationalist Faction had broken the lines of the Spanish Republican Army in the Aragon Offensive. Although seldom mentioned in historical works, it was one of the most protracted battles of the Civil War.
Text from the Wikipedia article Battle of the Segre, licensed CC BY-SA 4.0.