Battle of Ponza
1435 CE.
Shown on the map at 40.900°, 12.967°.
The naval battle of Ponza was fought in early August 1435, when the Duke of Milan dispatched the Genoese navy to relieve the besieged town of Gaeta, which was currently under threat from the King of Aragon.
Text from the Wikipedia article Battle of Ponza (1435), licensed CC BY-SA 4.0.