In the Vulgate Merlin, a stronghold near Garlot, to which Queen Blasine of Garlot tried to flee after the Saxons besieged her city. She was captured by Saxons along the way, but later was rescued by Gawain.
The fortification supposedly took its name because Vortigern was rescued there from an attack by Hengist, who was slain. This account of Hengist’s death conflicts with earlier tales, including one in the same text.
Source
Vulgate Merlin | 1220-1235