Siege of Megalopolis
316 BCE.
Shown on the map at 37.400°, 22.133°.
The siege of Megalopolis was a siege battle during the Second War of the Diadochi between Polyperchon, the Regent of the Macedonian Empire, and the people of Megalopolis who supported Polyperchon's rival Cassander. The siege failed and Polyperchon lost a lot of prestige, which was capitalized on by Cassander and his ally Antigonus.
Text from the Wikipedia article Siege of Megalopolis, licensed CC BY-SA 4.0.