Battle of Andernach
876 CE.
Shown on the map at 50.439°, 7.406°.
The First Battle of Andernach between the West Frankish king Charles the Bald and the East Frankish king Louis the Younger took place on 8 October 876 near Kettig southeast of Andernach and resulted in Charles' defeat.
Text from the Wikipedia article Battle of Andernach (876), licensed CC BY-SA 4.0.