Battle of Cadfan
1257 CE.
Shown on the map at 51.884°, -3.995°.
The Battle of Cadfan was fought between English and Welsh forces in 1257. The battle consisted of two military engagements; one at Coed Llathen and the other at Cymerau. The word Cadfan is Welsh for "place of battle".
Text from the Wikipedia article Battle of Cadfan, licensed CC BY-SA 4.0.