Battle of Kelja
1939 CE.
Shown on the map at 60.675°, 30.245°.
The Battle of Kelja, fought from December 25 to December 27, 1939 in and around the village of Kelja (now Portovoe, Priozersky District, Leningrad Oblast, Russia), was a part of the Winter War between Finland and the Soviet Union.
Text from the Wikipedia article Battle of Kelja, licensed CC BY-SA 4.0.