DescriptionCastle Hills is a well-preserved example of a motte and bailey castle which will retain buried evidence of its original timber structures and other deposits created during its medieval occupation. Its reuse in the 20th century as part of the defences for RAF Catterick adds to its importance, individual structures being of interest in their own right. The Light Anti-aircraft gun emplacement is a particularly rare survival and is considered to be of national importance.
The monument includes earthwork and associated buried remains of a medieval motte and bailey castle along with the standing and earthwork remains of a group of 20th century defences constructed to defend RAF Catterick. A further sample of the World War II airfield defences, lying to the south of the airfield, are the subject of a separate scheduling. The monument is located on the west side of the River Swale, to the east of the former RAF airfield.
In the medieval period, the motte and bailey castle lay in an outlying part of the manor of Catterick known as Killerby. This was held by a man named Scholland who is thought to have built the castle in 1120-25 to control a fording point across the River Swale. Scholland was sewer, one of the senior servants, to Count Alan Niger of Richmond. However it has also been suggested that the castle was remodelled from an earlier defensive site dating to before the Norman Conquest. The motte and bailey castle is thought never to have acquired masonry structures, but remained an earthwork and timber fortification. It passed through the same family until 1291 when it was abandoned by Brian Fitz-Alan of Killerby for a new stone castle just over 1km to the south east. In the 20th century, the high ground provided by the motte and bailey castle was again used defensively. In 1940-41 RAF Catterick was provided with airfield defences against attack by low flying aircraft and ground assault by troops, with the motte and bailey forming the main defensive strong-point. The remains of these defences are also included in the monument.
The motte and bailey castle forms a small area of higher ground on the western side of the River Swale's floodplain, the eastern flank of the castle being a continuation of an abandoned river cliff. It can be roughly divided into three parts, an outer ward in the southern part of the monument, the bailey at the centre and the motte in the north eastern part. The outer ward is a gently sloping, south facing enclosure about 60m by 80m, defined by the abandoned river cliff to the east and by old embanked hedge lines to the south and west. At the time that the castle was occupied, this area would have typically included some auxiliary buildings and probably have been used for activities such as blacksmithing. Along the southern side of this enclosure there are the platforms for a group of small buildings once part of the dispersed layout of RAF Catterick. On the north side of the outer ward, the slope steepens, marking the line of the southern rampart of the bailey and to the north west there is the southern part of a deep, broad moat ditch. This moat continues northwards, enclosing the western side of the bailey to meet the moat that encircles the motte.
The bailey is an irregular, but roughly triangular area some 80m across. Around its edge there is evidence of a raised rampart, particularly on the western side, with its corners rising higher as definite mounds. This defended bailey at Castle Hills is considered to have included the castle's great hall, main apartments and other important buildings such as kitchens. The three mounds at the corners of the bailey were all modified in the 20th century. The south eastern mound is topped by a thickened type 22 pillbox for five Lewis or Bren machine guns. Hexagonal in plan, it has 24 inch (0.6m) thick walls constructed with an outer and inner cladding of brick over reinforced concrete. Internally it has an anti-ricochet wall with an iron ladder leading to a central hatchway in the roof. This provided access to a Light Anti-aircraft (LAA) gun position on top of the pillbox. Surmounting the south western mound is a concrete emplacement for another LAA gun. This emplacement, believed to have been for a 40mm Bofors gun, includes ammunition lockers that retain some surviving timber fittings. This LAA gun position is thought to have been sited so that it could also cover the airfield to prevent the successful landing of enemy troops. In the top of the north eastern mound is a shallow hollow which is interpreted as an infantry foxhole. Further probable foxholes lie on a terrace part way down the slope on the western side of the bailey.
To the north east of the bailey, surrounded by a broad moat, part of which frequently holds water, is the motte. This conical mound is around 50m-60m diameter at its base and about 10m-15m across at its summit. It forms the highest part of the monument, with extensive views across the surrounding countryside. It would have originally been topped by a timber tower or fortified enclosure, some buried footings for which are expected to survive. This vantage point was also reused in the 20th century and it retains a small trench system constructed upon its summit, with further foxholes on its northern flank.
To the south west of the motte, on the western boundary of the monument, there is a boundary stone with the inscription AM No13. This stone, which is also included in the monument, is one of at least 25 individually numbered boundary stones erected by the Air Ministry in 1925-27, and marks where the boundary of RAF Catterick changed direction. (Scheduling Report)
