The Battle of Aegospotami (405 B.C.)

The The Battle of Aegospotami (405 B.C.), a great naval victory of Sparta over Athens, effectively ended the Peloponnesian War. The fleets of the two Greek rival powers faced each other in the Hellespont for four days without battle, until on the fifth day the Spartans under Lysander surprised the Athenians in their anchorage off Aegospotami. Conon, the Athenian commander, escaped with only 20 of his 180 ships, and the 3,000-4,000 Athenians who were captured were put to death.

The victory at Aegospotami enabled Lysander to proceed against Athens itself, forcing the Athenians to surrender in April 404. (Encyclopaedia Britannica Online.)