Battle of Sphacteria
424 BCE.
Shown on the map at 36.930°, 21.666°.
The Battle of Sphacteria was a land battle of the Peloponnesian War, fought in 425 BC between Athens and Sparta. Following the Battle of Pylos and subsequent peace negotiations, which failed, a number of Spartans were stranded on the island of Sphacteria. An Athenian force under Cleon and Demosthenes attacked and forced them to surrender.
Text from the Wikipedia article Battle of Sphacteria, licensed CC BY-SA 4.0.