From the National Heritage List of England: Details The monument falls into two areas of protection and includes a Benedictine monastic grange and an earlier, pre-Conquest nunnery situated on low-lying ground near the eastern edge of the town of Minster, on the Isle of Thanet. Until around the 14th century, Minster lay on the north eastern shore of the Wantsum Channel, a now silted-up estuarine waterway which separated Thanet from the Kent mainland. The nunnery is represented by below ground traces of buildings and associated remains, which will survive beneath the later monastic grange. Minster nunnery was first founded by Domneva, niece of Egbert, King of Kent, and her daughter St Mildred, in AD 670, on the site now occupied by Minster parish church around 150m to the south west of the monument. Historical records suggest that the religious house was moved in AD 741 by the third Abbess, St Edburga, when the original site became overcrowded. By this time the nunnery housed around 70 nuns. The new church was dedicated to St Peter and St Paul. Viking raids caused much disturbance to this part of Kent from the late eighth century, and the nunnery is reported to have been burnt to the ground, and many of the nuns massacred, in AD 840. In AD 1027 King Canute granted the by then deserted nunnery and its lands to the Benedictine monks of St Augustine's Abbey, Canterbury. They constructed the monastic grange, which operated as the main administrative centre for their large, mainly arable farmlands then covering most of Thanet. The grange survives in the form of standing buildings, water-filled fishponds and associated below ground remains. Lying towards the centre of the south western area of protection, the main grange buildings were arranged around a square, east-west aligned courtyard. The standing buildings are Listed Grade I and incorporate the northern hall range and attached western range, along with the ruined fragment of a square tower which adjoins the southern end of the western range. Faced with rubble ragstone and flint with ashlar dressings, the buildings have been dated by their architectural details to the 11th and 12th centuries. Original features include courses of herringbone walling and some Norman doorways and windows. The main accommodation in the north and west ranges was originally on the first floor over vaulted undercrofts. The attached tower was three-storeyed, and its massively thick walls indicate that it had an at least partly defensive purpose. A large-scale programme of alteration and renewal was carried out for Abbott Thomas Hunden in 1413, and the buildings underwent subsequent phases of alteration during the 17th, 19th and 20th centuries. The standing medieval buildings have been in use as a modern Benedictine nunnery since 1937 and are therefore excluded from the scheduling although the ground beneath is included. Investigations carried out in 1929-30 revealed the foundations of a demolished Norman church which formed the southern range of the main courtyard. This was attached at its western end to the square tower. Around 50m to the west of the main courtyard is a small rectangular building, in use as a modern laundry, which incorporates medieval walling representing the grange brewhouse. This building is Listed Grade II and excluded from the scheduling, although the ground beneath is included. Surrounding the grange to the south, south west and east, is a 19th century wall which incorporates a 19th century gatehouse in its eastern side. The wall and gatehouse are excluded from the scheduling, although the ground beneath is included. The monastic grange had been leased as a secular farmhouse by the time of the Dissolution of the Monasteries, and was used for this purpose throughout the post-medieval period. The construction of a number of 19th and 20th century buildings within the monument will have caused some disturbance to the archaeological remains. These buildings are excluded from the scheduling, although the ground beneath them are included. Medieval wall footings, indicating the presence of further, now demolished Norman buildings, were discovered during the construction of a new, detached modern chapel in 1993 to the east of the main northern range. Further buried traces of the monastic grange will survive in the areas between and around the known medieval buildings. Situated to the north east are a group of three rectangular, linked, north- south aligned fishponds, which helped to supply the medieval grange with fresh fish. These have been partly disturbed by modern landscaping. A number of features are excluded from the scheduling; these are the buildings of Minster Abbey, in use as a modern nunnery, the 19th century wall to the south, south west and east and the 19th century gatehouse, all modern garden structures and features, the modern surfaces of all paths, tracks, hardstanding and paving; the ground beneath all these features is, however, included. Reasons for Designation A monastic grange was a farm owned and run by a monastic community and independent of the secular manorial system of communal agriculture and servile labour. The function of granges was to provide food and raw materials for consumption within the parent monastic house itself, and also to provide surpluses for sale for profit. The first monastic granges appeared in the 12th century but they continued to be constructed and used until the Dissolution. This system of agriculture was pioneered by the Cistercian order but was soon imitated by other orders. Some granges were worked by resident lay-brothers (secular workers) of the order but others were staffed by non-resident labourers. The majority of granges practised a mixed economy but some were specialist in their function. Five types of grange are known: agrarian farms, bercaries (sheep farms), vaccaries (cattle ranches), horse studs and industrial complexes. A monastery might have more than one grange and the wealthiest houses had many. Frequently a grange was established on lands immediately adjacent to the monastery, this being known as the home grange. Other granges, however, could be found wherever the monastic site held lands. On occasion these could be located at some considerable distance from the parent monastery. Granges are broadly comparable with contemporary secular farms although the wealth of the parent house was frequently reflected in the size of the grange and the layout and architectural embellishment of the buildings. Additionally, because of their monastic connection, granges tend to be much better documented than their secular counterparts. No region was without monastic granges. The exact number of sites which originally existed is not precisely known but can be estimated, on the basis of numbers of monastic sites, at several thousand. Of these, however, only a small percentage can be accurately located on the ground today. Of this group of identifiable sites, continued intensive use of many has destroyed much of the evidence of archaeological remains. In view of the importance of granges to medieval rural and monastic life, all sites exhibiting good archaeological survival are identified as nationally important. Nunneries were built to house communities of women living a common life of religious observance under systematic discipline. Although varying considerably in the detail of their appearance and layout, all nunneries include the basic elements of church, accommodation for the community and work buildings. At the focus is the main cloister, comprising the church and main domestic buildings arranged around an open cloister yard. This would often be accompanied by subsidiary courts and a gatehouse. The complex was enclosed by a precinct wall, fence, moat or ditch. Associated fishponds, mills, field systems, stock enclosures and barns might be situated beyond the precint, within the often large estate held by the religious house. The earliest English nunneries were founded in the seventh century AD, although most of these had fallen out of use by the ninth century. A small number of the earliest houses were refounded in the later medieval period. Most post-Conquest nunneries were established from the late 11th century onwards. Nunneries were established by most of the major religious orders of the time, including the Benedictines, Cistercians, Augustinians, Franciscans and Dominicans. It is known from historical sources that only 153 nunneries existed in England, of which the precise locations of around 100 are known. Few nunneries have been investigated in detail, and as a rare and poorly understood medieval monument type all examples exhibiting survival of archaeological remains are worthy of protection. The monastic grange at Minster Abbey survives exceptionally well and is a rare, early example of this type of monument, retaining 11th and 12th century standing buildings of high architectural quality and other visible components. Part excavation has confirmed that the monument also retains important, below ground archaeological and environmental evidence relating to its original form, development and use. The grange is the most important and one of the best surviving examples of a group of contemporary Benedictine monastic granges which cluster on the Isle of Thanet, illustrating the control exercised over this part of Kent by St Augustine's Abbey, Canterbury during the medieval period. The underlying, pre-Conquest nunnery is a comparatively well documented example of one of the earliest English religious houses. The close association between the monastic grange and the earlier nunnery will provide important evidence for medieval religious life over a period of around 800 years.