Battle of Mön
1657 CE.
Shown on the map at 54.953°, 13.031°.
The indecisive naval battle of Møn was a battle during the Dano-Swedish War (1657–1658). A large number of ships was involved, but the fight was not very intense.
Text from the Wikipedia article Battle of Møn (1657), licensed CC BY-SA 4.0.