Thornton Abbey is an important example of a wealthy Augustinian monastery and unusual in that it survived in use after the Dissolution as a secular college. Although, in the main, its standing remains do not survive well, having been systematically quarried after the college was suppressed, the foundations of a wide variety of monastic buildings are still in place and provide a good illustration of the layout of this type of monastery. The gatehouse and barbican, which survive almost intact, are the best preserved of any monastery in the country. Furthermore, the buried remains of other buildings and features survive in the extensive precinct which is still defined by its original encircling moat. Together with a complex system of fishponds and other water-management works, these will provide importance evidence of the economy and way of life peculiar to Augustinian canons. The site is unusual in having very good documentary evidence contained within a 16th century Chronicle and a 1539 Augmentation Survey. These provide excellent detail of individual buildings. Such detailed documentation is rare for an Augustinian house and considerably improves our understanding of it.
Thornton Abbey is situated in Lindsey, south of the Humber estuary, and was formerly in the county of Lincolnshire. The monument comprises a single area which contains the late fourteenth century gatehouse and barbican of the Augustinian monastery, an outer precinct surrounded by a moat and containing the earthwork remains of a wide variety of ancillary features and buildings, the walled inner precinct containing the foundations of the abbey church and other cloister buildings and the buried remains of additional structures, the site of the medieval road that predated the abbey, the remains of the fourteenth century bridge that underlie modern College Bridge, and a large number of monastic fishponds. In addition, after the Dissolution of the Monasteries, Henry VIII refounded the abbey as a college of secular priests and a school for fourteen boys, re-using buildings of the former monastery. This college was suppressed by Edward VI in 1547 and demolished by Sir Vincent Skinner in 1610. Out of the remains, Skinner built a stately house which subsequently collapsed. The site of this house also lies within the inner precinct. The best preserved standing remains are of the abbey gatehouse. This is a three storey structure built largely of brick and originally rendered with white mortar. It was built in the 1360s and enlarged and defended after licence to fortify was granted to the abbey in 1382 and appears to have had an administrative function since it contained the Abbot's exchequer and courthouse. Three floors were built above a central gate-passage. The first housed a great hall with a fireplace and an oriel window. The second and third contained a complex of passages and rooms and included a large room on the second floor originally divided by wooden partitions. In addition there were eight privies and a latrine. The gate-passage underneath is vaulted and leads at the rear to two original oak gates which date to the fourteenth century. The front of the gatehouse is richly ornamented but has lost most of its battlements on which originally stood statues of men-at-arms and artisans. Other statues stood in niches on the front wall and a number of these survive. Approaching the gatehouse from the front is a barbican consisting of two parallel brick walls 38m long and ending in round turrets. This was built c1382 and is believed to have ended in a drawbridge which led over a now filled-in extension of the moat. It incorporates the remains of an earlier bridge across the moat. Wing-walls flank the gatehouse to north and south and turn at right-angles to enclose the inner precinct. The moat is at its widest in front of the gatehouse where it measures c 20m across and is still partially water-filled. It extends for c 300m to north and south then turns east for c 400m to meet East Halton Beck, enclosing a precinct of c 29 hectares. Fed by the moat are at least two separate groups of fishponds. The northernmost group lies north-east of the church. The southernmost lies outside the south-east corner and consists of a small detached pool adjacent to a group of three small pools and one larger surrounded by a moat. An arm of the main moat which crosses the precinct north of the gatehouse may also have served as a fishpond, as may a similar ditch crossing south of the cloister buildings. A number of other ditches can be seen crossing the precinct and are part of the system of water-management works which served the monastery. An extensive survey of the earthworks visible in both the inner and outer precincts indicates the survival of walled or ditched enclosures and the foundations of many buildings of various sizes in addition to smaller enclosures or pens. None of these have been excavated and so their functions cannot yet be precisely determined. However, they will undoubtedly conform to the usual range of monastic ancillary buildings and include, for example, storehouses, workshops, and barns. Documentary evidence already points to the existence at Thornton Abbey of barns, granaries, a brewhouse and bakehouse, an extensive guesthouse and possibly also a mill. It is also clear that the home grange (or chief monastic farm) lay in the north of the area of the scheduling. Many of the other documented buildings will lie within the walled inner precinct which also contained the abbey church and cloister buildings. Although little remains standing of the cloister buildings, the foundations remain and were excavated by Charles, first Earl of Yarborough in the 1830s. Much of the ground-plan was thus uncovered and a typical monastic layout revealed. However, excavation was not carried out below the level of the latest remains and so details of the layout of the first cloister and church, built at the monastery's foundation, are, at present, not understood. The earliest visible remains are of the vaulted undercroft of the east cloister range. These date to the early thirteenth century and indicate a range of small rooms, one of which has been interpreted as the warming house. These stood beneath the first floor dorter or monk's dormitory. A passage or slype separated the warming house from the rest of the range until it was blocked in the fifteenth century or later. North of the undercroft are the late thirteenth century remains of the vestibule and a narrow room interpreted as the parlour, where necessary conversation was permitted. The vestibule leads into the chapter house which is still partially standing. This octagonal structure was begun in 1282 and was floored in 1308. The surviving walls are decorated with window tracery which is assumed to have mimicked actual windows in the sides which are no longer standing. The remains of the stone seat which lined the walls of the chapter house can be seen on either side of the entrance into the vestibule. The north range of the cloister comprised, as was usual, the abbey church. The surviving foundations indicate a late thirteenth century building with alterations made to the nave in the early fourteenth century when another aisle, the southern, was added. A chapel dedicated to St Thomas of Canterbury (Becket) was built off the north side of the presbytery at this time and a Lady Chapel was built behind the high altar later in the same century. The early fourteenth century alterations to the nave were made at the same time as the building of two new cloister ranges, the west and south, begun in 1322-3. These almost certainly replaced earlier buildings, the foundations of which will survive beneath the visible remains of the later. The fourteenth century west range consisted of a vaulted undercroft of seven double bays. This would have been used for storage and the first floor rooms above would have been either lay-brothers' accommodation or possibly the lodgings of the earlier abbots. A second roughly identical undercroft, formed the ground-floor of the south range which would have housed the monks' frater or refectory on the first floor. The remains of other cloister buildings have not yet been excavated but these will include an infirmary, often found to the east of the east range adjacent to the abbey cemetery, kitchens which were usually built to the south of the south range, and the reredorter or latrine which usually adjoined the dorter (dormitory). Prior to the foundation of the abbey, a road ran through the area that was to become the monastic precinct. When the monastery was established, this road was diverted round the north side of the precinct along its current route but the remains of the pre-monastic road will survive in the precinct. In addition, where the later road crossed East Halton Beck a bridge was built and has been rebuilt on the same site down to the present day. Incorporated into the modern structure are the substantial remains of a fourteenth century bridge. The monastery was founded as a priory in 1139 by William LeGros, Count of Aumale, and was raised to the status of abbey in 1148. It was colonised by twelve black canons from the Augustinian priory at Kirkham in North Yorkshire and became one of the richest Augustinian houses in the country. As noted above, after its suppression in 1539, Henry VIII refounded it as the College of the Holy Trinity whose establishment was part of the King's plan to create new dioceses and secular schools whose purposes included the ministration of the sacraments and the education of young boys. The college lasted only six years, however, then the gatehouse and a number of other buildings were granted to Henry Randes, Bishop of Lincoln, who went on to acquire the whole site freehold. In 1575, his son sold it to Sir Robert Tyrwhitt whose own grandson sold it in 1602 to Sir Vincent Skinner. An account of Abraham de la Pryme, written in 1692, indicates that Skinner demolished the buildings and from the stone built a house on the west side of the abbey plot within the moat; that is, inside the abbey precinct. This house is said to have collapsed without visible cause. Skinner then built another house on the site. Trenches north-east of the gatehouse, dug when building stone was removed from the site, are thought to indicate the position of one of the Skinner houses. In 1720, the site passed to Sir Robert Sutton, in 1792 to George Uppleby and, in 1816, to Charles, First Lord Yarborough whose son carried out the excavations of the cloister ranges. The gatehouse and cloister buildings have been in State care since 1938. They and the Barbican, precinct walls, remains of the church and Abbot's Lodge are Grade I Listed, while the coachhouse and the ruins of the south precinct gateway, the garden and orchard walls and the bridge are Listed Grade II. (Scheduling Report)
Abbey gatehouse and wing walls, precinct walls and barbican. Gatehouse and wing walls of 1382 for Abbot Thomas Gresham, with later C14-C15 extensions to wing walls and precinct walls; C15-C16 barbican. C20 renovations, including replacement of gatehouse chamber floors. Gatehouse of brick with limestone ashlar dressings and decorative details; limestone and ironstone ashlar facing to plinth, turrets, lower stage of central front section and central section to rear. Wing walls of brick with ashlar dressings, extended in squared chalk with ashlar dressings and outer brick facing. Precinct walls of squared chalk and chalk rubble with outer brick facing. Barbican of brick with chalk and limestone ashlar dressings. Plan; rectangular gatehouse with angle turrets has main central passage with foot passage branching to right and single rooms either side. Wing walls with round mid-wall turrets and square outer turrets continue as precinct walls extending c125 metres south and c40 metres north to base of outer square turret. Barbican c38 metres long across moat in front of gatehouse. Gatehouse of 3 storeys, 3 bays, has 2-stage front with projecting octagonal turrets at angles and between bays, flanked by 2-bay wing walls, the inner bays sloping down to 3-storey round towers and the wider outer bays extending down to single-storey square turrets. Barbican of 15 bays with round turrets flanking entrance. Gatehouse: pointed entrance arch of 3 shafted orders with a cusped segmental outer arch flanked by blank bays with segmental arches supporting corbel table and outer wall passage. Upper stage has two tiers of elaborate canopied niches, some retaining carved figures, corbel table and fragmentary embattled parapet. Central passage has unusual pointed tunnel vault with longitudinal ridge-rib flanked by intersecting diagonal ribs springing from small wall shafts with foliate capitals. Inner arch of 2 orders with upper sections of original 2-fold oak doors with carved reticulated tracery. Pedestrian side passage has two sections of similar ribbed vaulting. Gatehouse inner face has plinth, moulded stringcourses between floors; pointed main arch of 3 orders, segmental-pointed arches to side bays; four-centred arch doorways, that to left turret with shafts and fleuron frieze above; first floor oriel window, 2-, 3- and 4-light traceried windows and corbel table beneath parapet. Interior contains first floor hall with fireplace, carved corbels for ceiling beams, moulded arch and ribbed vaulting to oriel window; series of wall passages and chambers, turret staircase ceiling with cusped and traceried ribs. Wing walls: ashlar plinth, moulded string courses, cornice and arrow slits to inner bays and round turrets; chamfered brick plinth and string courses to outer bays and square turrets; blind pointed arches on inner face, internal galleries and turret chambers. Barbican: roadway flanked by pointed blank arches with cruciform arrow slits, cogged brick cornice and fragmentary remains of crenellations; turrets with chamfered ashlar plinths contain round chambers with corbelled ceilings, chamber to left with adjoining garderobe. The largest and one of the most impressive gatehouses in England, notable for its use of brick, ambitious design and rich ornamentation. (Listed Building Report)
The best preserved standing remains of Thornton Abbey are of its gatehouse. This is a three storey structure built largely of brick with limestone ashlar dressings and decorative details. It was built in the 1360s and enlarged and defended after licence to fortify was granted to the abbey in 1382 and appears to have had an administrative function since it contained the Abbot's exchequer and courthouse. Three floors were built above a central gate-passage. The first housed a great hall. The second and third contained a complex of pasages and rooms. The gatehouse underneath is vaulted at the rear to two original oak gates which date to the 14th century. The front of the gatehouse is richly ornamented but has lost most of its battlements on which originally stood statues of men-at-arms and artisans. Approaching the gatehouse from the front is a barbican consisting of two parallel brick walls 38 metres long and ending in round turrets. This was built circa 1382 and is believed to have ended in a drawbridge which led over a now filled-in extension of the moat. Wing-walls flank the gatehouse to the north and south and turn at right-angles to enclose the inner precinct. (PastScape)