Details The monument includes an enclosure castle situated on a gentle east facing slope in an area of Greensand. The castle has ruined upstanding remains of medieval masonry dating from about 1300, surrounded by a partially infilled circular moat. The enclosed central area of the castle measures c.48m in diameter and contains the remains of the enclosing wall, which constituted the castle's main defence, with the gateway entrance on the north east side. The gatehouse is formed by two drum towers which survive to the first floor level. These incorporate a number of features including arrow-loops, external portcullis grooves and a water chute above the entrance way. Within the eastern tower is a well. On the south eastern edge of the enclosed area are the remains of a mural tower which survives up to c.7m high and appears to be contemporary with the gatehouse. On the west side of the interior inside the enclosing wall is a rectangular building 11m north-south by 6m east-west, thought to be a chapel. Although the building may incorporate some of the earlier construction of the castle, it is believed to relate to the private house which was built within the castle ruins during the 16th century. Surrounding the central area is a moat, visible to the north, west and south as an earthwork up to 15m wide and 1m deep. To the east the moat has become infilled and is no longer visible from ground level, surviving as a buried feature. An entrance causeway crosses the moat to the north east. There is little documentary evidence which records the earliest history of Leybourne Castle but it has been suggested that the castle was originally Norman, dating to the 11th or 12th century. The majority of the upstanding masonry, however, dates to the early 14th century and the gateway was built during the reign of Edward III. The 16th century house, erected in the ruins of the castle, remained until 1930 when the present house was built along the eastern line of the castle wall. Leybourne Castle ruins are Listed Grade II*, but are nevertheless included in the scheduling except where incorporated into the modern house. Excluded from the scheduling are the modern inhabited house, fences, fence posts and gates, although the ground beneath all these features is included. Reasons for Designation An enclosure castle is a defended residence or stronghold, built mainly of stone, in which the principal or sole defence comprises the walls and towers bounding the site. Some form of keep may have stood within the enclosure but this was not significant in defensive terms and served mainly to provide accommodation. Larger sites might have more than one line of walling and there are normally mural towers and gatehouses. Outside the walls a ditch, either waterfilled or dry, crossed by bridges may be found. The first enclosure castles were constructed at the time of the Norman Conquest. However, they developed considerably in form during the 12th century when defensive experience gained during the Crusades was applied to their design. The majority of examples were constructed in the 13th century although a few were built as late as the 14th century. Some represent reconstructions of earlier medieval earthwork castles of the motte and bailey type, although others were new creations. They provided strongly defended residences for the king or leading families and occur in both urban and rural situations. Enclosure castles are widely dispersed throughout England, with a slight concentration in Kent and Sussex supporting a vulnerable coast, and a strong concentration along the Welsh border where some of the best examples were built under Edward I. They are rare nationally with only 126 recorded examples. Considerable diversity of form is exhibited with no two examples being exactly alike. With other castle types, they are major medieval monument types which, belonging to the highest levels of society, frequently acted as major administrative centres and formed the foci for developing settlement patterns. Castles generally provide an emotive and evocative link to the past and can provide a valuable educational resource, both with respect to medieval warfare and defence and with respect to wider aspects of medieval society. All examples retaining significant remains of medieval date are considered to be nationally important. Leybourne Castle survives comparatively well despite the later construction of a house within the defences. Large areas of the ward and surrounding moat have remained undisturbed and contain both archaeological remains and environmental evidence. These will provide an insight into the construction of the castle as well as the economy and way of life of the inhabitants of a 13th century enclosure castle.