The Castle of Folkestone is mentioned in a charter of c.1137. Hasted records that it was the main seat of the barony, and that in his day it was all destroyed by erosion, except for a small length of ancient wall on the east side of its bail or precinct. During excavation work by the Department of Archaeology from York University a major ditch was located containing pottery from the late 10th - early 12th century (late Saxon to "Saxon-Norman" Canterbury sandy wares). This ditch is in all probability the boundary to the "Castel Yard" as recorded by Leland in 1576 and on later 17th and 18th century estate maps in a much altered form of costal fortification. A late 11th to early 12th century date for this feature is given some support by the first recorded mention of the "castello de Folkestan" in a charter of confirmation granted by (1138AD) by William de Averenches to the monks of Folkestone Priory.