Battle of Amphipolis
421 BCE.
Shown on the map at 40.824°, 23.847°.
The Battle of Amphipolis was fought in 422 BC during the Peloponnesian War between Athens and Sparta. It was the culmination of events that began in 424 BC with the capture of Amphipolis by the Spartans.
Text from the Wikipedia article Battle of Amphipolis, licensed CC BY-SA 4.0.