Burh-fæsten

According to the Old English Dictionary:

es;

burh-fæsten

n. A city-fastness, fortress, citadel; arx munita, castellum :-- Com God sceáwigan beorna burhfæsten God came to view the chieftains' city-fastness, Cd. 80; Th. 101, 10; Gen. 1680. burh-fæsten