Trematon Castle, a shell keep built on a motte and bailey castle


Heritage Category:
Scheduled Monument
List Entry Number:
Date first listed:
Location Description:
Legacy Record - This information may be included in the List Entry Details.


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The building or site itself may lie within the boundary of more than one authority.

Location Description:
Legacy Record - This information may be included in the List Entry Details.
Cornwall (Unitary Authority)
National Grid Reference:
SX 41036 57964

Reasons for Designation

Motte castles are medieval fortifications introduced into Britain by the Normans. They comprise a large conical mound of earth or rubble, the motte, surmounted by a palisade and a stone or timber tower. In the majority of examples an embanked enclosure containing additional buildings, the bailey, adjoined the motte. Motte castles and motte and bailey castles acted as garrison forts during offensive military operations and as strongholds. In many cases they were aristocratic residences and the centres of local or royal administration. Between the Conquest and the mid 13th century, usually during the 12th century, a number of motte and bailey castles and ringworks were remodelled in stone. In the case of mottes, the timber palisade was replaced by a thick wall to form a `shell keep'. If the tower on the motte was of timber, this may also have been replaced in masonry and, if a bailey was present, its ramparts were often strengthened with a curtain wall. Within the keep, buildings for domestic or garrison purposes were often constructed against the inside of the keep wall. Although over 600 motte castles or motte and bailey castles are recorded nationally, examples converted into shell keeps are rare with only about 60 sites known to have been remodelled in this way. As such, and as one of a restricted range of recognised post-Conquest monuments, they are particularly important for the study of Norman Britain and the development of the feudal system. Despite some later modification caused by the creation of garden features and the insertion of a house within the bailey, Trematon Castle survives well retaining many original upstanding features and further buried structures and deposits. It will contain archaeological and environmental evidence relating to its construction, longevity, trade, military, political, social and economic significance, domestic arrangements, abandonment, re-use and overall landscape context.


The monument includes a shell keep built on a motte and bailey castle situated at Forder, overlooking a navigable length of a branching coastal estuary close to the confluence of the St Germans or Lynher River with the River Tamar. The castle survives as a large steep-sided circular mound or motte with an oval stone-built shell keep on the summit. An oval bailey adjoining the motte to the south west is defined by a rampart topped with a curtain wall and includes a gatehouse, all surrounded by an outer ditch preserved as a largely buried feature. The shell keep was built in the 12th century and stands to parapet level with traces of inner buildings. The gatehouse was rebuilt in the 13th century and, although it has a modern roof, is largely complete. Much of the curtain wall also stands to wall walk or parapet level apart from a section which was removed in 1807-8 to improve the view when Higher Lodge (Listed Grade II*) was built within the bailey. A small grotto was cut into the rock at the base of the motte as a garden feature around this time. The castle, mentioned in Domesday, was bought by Richard, Earl of Cornwall in 1270 and was bestowed on the Black Prince in 1337. It was granted out from 1392 - 1443 and then returned to the Crown. It was reported as ruinous by the 16th. An accompanying deer park, named in 1282, had been lost by 1500. The garden features and structures, paths and driveway surfaces and the house are excluded from the scheduling, but the ground beneath these features is included. A section of crenellated and probably later wall (60436) and a medieval arched doorway (60435) are Listed Grade II.

Sources: HER:- PastScape Monument No:-437464


The contents of this record have been generated from a legacy data system.

Legacy System number:
CO 578
Legacy System:


This monument is scheduled under the Ancient Monuments and Archaeological Areas Act 1979 as amended as it appears to the Secretary of State to be of national importance. This entry is a copy, the original is held by the Department for Digital, Culture, Media and Sport.

End of official listing

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