DescriptionThe remains of the motte and bailey castle at Castle Bytham survive in good condition. Part excavation of the site in the 19th century demonstrated the high level of survival of structural and artefactual remains while leaving the majority of deposits intact. The castle itself is of a particularly rare type in having an internal barbican, one of very few examples in this country; the construction, occupation and siege of the castle are well documented and provide the opportunity to identify specific archaeological deposits with recorded historical events. The water control system and settlement defences associated with the castle are outstanding in Lincolnshire and survive in excellent condition, having been relatively unaltered since medieval times. The archaeological relationships between the complementary elements of the castle will show us how a high status establishment of this type functioned, both as a defensive system and as an economic, social and symbolic force in the local and regional landscape.
The monument includes Castle Bytham Castle, a motte and bailey castle believed to have been constructed in the late 11th century by Drogo, brother-in-law of William I. The castle is first directly referred to in documentary sources of the later 12th century, when it was held by William, 3rd Earl of Albemarle; soon after it was granted to William de Colvile, and then in 1215-16 to William de Fortibus. In the winter of 1220-21 Fortibus fortified the castle against King Henry III, who successfully besieged it and ordered its destruction. The manor was returned to the Colviles, who rebuilt and re-occupied the castle until the late 14th century when it was inhabited by Lady Basset, grandmother of Henry V. In the 15th century it fell into decline and by 1544 was in ruins; it was subsequently dismantled for building stone and by 1906 no stonework was visible above ground. The castle remains are located on a natural spur projecting westwards into the valley of the River Tham which runs from north to south east through the village. The motte is constructed on the tip of the spur while the bailey, which is L-shaped, lies on the high ground to the south and east of it. The earthwork remains of the castle are adjoined by those of an elaborate water control system constructed on the original course of the river and composed of a series of artificial channels and ponds linked by dams and sluices; this system served a combination of defensive, symbolic and economic functions associated with the castle, including fish rearing and milling. To the south west of this complex of earthworks is the site of a settlement contemporary with the castle, now occupied by the present village; on its south eastern side are the remains of part of a substantial stone wall by which it was formerly defended. The monument includes the earthwork and buried remains of the motte and bailey castle, its water control system and the defences of its associated settlement, which are protected within three separate areas. The motte takes the form of a conical flat topped mound standing to a height of approximately 18m above the river valley. The top of the mound, which is oval, is wholly occupied by the remains of a quadrangular shell keep. These remains take the form of earth covered stone walls defining a series of rooms of largely rectangular shape ranged around a central courtyard. The ranges vary in width, the most substantial structures being to the west and south. Depressions in the south range indicate the presence of basements which are thought to have been part of a strong tower or donjon. Structures extending southwards from the south range onto the side of the motte include the remains of a postern gate which were partly excavated in the 19th century. The principal gateway to the keep was situated at the south eastern corner where there is an opening leading eastwards from the central courtyard and passing between the remains of two substantial stone towers built onto the side of the motte. The motte is surrounded by a deep ditch with, on three sides, a large external bank surmounted by the remains of a stone curtain wall which incorporates mural towers at its south western and north western corners. To the east of the motte, and connected to it by a narrow causeway across the ditch, is a mound of similar height; the top, which measures about 10m in diameter, is occupied by the earth covered remains of a hexagonal tower. This tower is identified as an internal barbican which served as an additional defence between the motte and the bailey. The barbican is also surrounded by a ditch, separated from that of the motte by an earthen bank which at each end meets the remains of a gateway in the curtain wall; that on the north leads directly onto the bailey, while that on the south leads over another ditch which runs along the south side of both the motte and the barbican. Standing on the high ground to the south and east of the motte are the earthwork remains of the bailey, an area of reversed L-shape about 50m wide on the east and 40m wide on the south. On the inner, north western edge are the remains of a stone wall; on the outer, south eastern edge it is protected by a substantial earthen bank and a wide external ditch. This ditch continues around the north and west ends, along which is a stone wall contiguous with the main curtain wall surrounding the motte. The bailey is divided into two parts by the remains of a stone wall running roughly east-west from the barbican ditch, with an entrance at its western end; to the north is a walled inner courtyard, and to the south a larger outer courtyard. In both courtyards are the earth covered remains of ranges of stone buildings, which are believed to have included domestic, agricultural and service buildings such as stables, barns, brewhouses and lodgings. The principal surviving entrance to the bailey is from the east where the remains of a large stone gateway lead into the outer courtyard from a causeway over the external ditch. The curtain wall along the northern end of the bailey is abutted to the north by the remains of a rectangular building which lies at right-angles to it on the inner scarp of the ditch; from the outside edge of the ditch a stone wall continues on the same alignment for a distance of nearly 80m to the river. The wall survives as an earthwork approximately 0.5m in height and terminates in a small mound about 1m high which is thought to represent the remains of a tower. Together, the wall and building serve as part of the defensive scheme of the castle. Running parallel with the wall at a distance of about 30m to the east are a linear bank and ditch marking a small rectangular enclosure associated with the castle, probably used for keeping animals. To the north and west of the motte and bailey earthworks is a low, flat area known as Castle Yard. This area represents the remains of a large pool constructed by channelling the river towards the western side of the valley and controlling the water level of the pool by a number of sluices. This pool formed part of a series of water control features contemporary with the castle which served to augment the defences both practically and symbolically and to provide water for a variety of economic activities. There are two causeways across the pool which would have been used in medieval and post-medieval times when the pool was dry. This water control system continues south of the castle where there are the earthwork remains of a large rectangular fishpond aligned east-west on the south side of the river and measuring approximately 50m by 30m, subdivided into two tanks by a rectangular central island. The pond, now dry, is about 3m deep; along its western side is a broad bank, up to 0.5m high and 10m wide, with an inlet channel at each end through which water was fed into the pond from the low ground on the west. There is another bank about 0.5m in height along the northern side of the pond. To the north west of the pond is a shallow rectangular depression, thought to be the remains of a smaller fishpond, and a raised platform where timber buildings associated with fish rearing are thought to have been located; to the east of the main fishpond is another depression about 0.5m deep which is believed to be part of another pond. To the south east of the castle are the earthwork remains of a second large pool, now dry, formed behind an earthwork dam built across the original course of the river. It is dammed at its southern end by a substantial earth and stone bank about 2m high, 50m long and 6m wide at the top; at its eastern end is a gap of about 5m, beyond which is a narrower, L-shaped bank meeting the scarp which defines the eastern side of the pool. The north end of this bank is overlain by a trackway. The western side of the pool is formed by a retaining bank approximately 1m high, and the eastern side by a levelled terrace built against the natural scarp. The pool formed behind the dam covered an L-shaped area at least 350m long and up to 80m wide. The damming of the pool is believed to date from the medieval period when a watermill associated with the castle is thought to have been situated at the dam, with the water wheel perhaps occupying the gap now left between the two banks. Running along the south and west sides of the pool is the water channel in which the river now runs; this is a man-made channel contemporary with the construction of the pool and served as a bypass leat to carry water away from the pool at times of increased flow. The north western part of the pool is bounded by a levelled terrace, including a trackway and building platforms believed to be medieval in origin. At the eastern end of the terrace are the earthwork remains of a small house and garden constructed in the early post- medieval period. Buildings in this area would have been associated with economic activity such as fish rearing or milling. The defensive scheme associated with the motte and bailey castle was completed in the medieval period by the construction of a 'town wall' to delineate and protect an area of settlement to the south west of the castle. Running south westwards up the slope from the fishpond complex is a linear bank, approximately 1.5m high and 6m wide, which represents the remains of this wall. It runs for over 160m to the edge of Station Road and then follows the edge of the road for approximately 14m to the earth covered remains of a small building. These features are thought to be associated with a gateway. (Scheduling Report)