Ancient Monuments

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Cas Troggy Castle

A Scheduled Monument in Shirenewton (Drenewydd Gelli-farch), Monmouthshire (Sir Fynwy)

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Latitude: 51.6526 / 51°39'9"N

Longitude: -2.8469 / 2°50'48"W

OS Eastings: 341503

OS Northings: 195203

OS Grid: ST415952

Mapcode National: GBR JD.70L3

Mapcode Global: VH7B2.LQSJ

Entry Name: Cas Troggy Castle

Scheduled Date: 11 January 1926

Source: Cadw

Source ID: 2960

Cadw Legacy ID: MM015

Schedule Class: Defence

Category: Castle

Period: Medieval

County: Monmouthshire (Sir Fynwy)

Community: Shirenewton (Drenewydd Gelli-farch)

Traditional County: Monmouthshire


The monument consists of the upstanding masonry remains and earthworks of a medieval castle begun for Roger Bigod III, Earl of Norfolk and Lord of Striguil (Chepstow) by 1303 on land acquired from the monks of Tintern Abbey and almost certainly abandoned soon after his death in 1306.

The surviving remains comprise a rectangular platform measuring 42m N/S by 27m E/W set on low ground close to a stream. There is a large pond on lower ground to the southern side of the platform but otherwise no sign of a moat on its other sides, in spite of the Cas Troggy Brook running immediately to its north. The southern side of the platform is occupied by the substantial ruin of a of a hall block with massive towers polygonal of typical ‘Edwardian’ construction at its SW and SE corners. All of the surviving external wall faces are of sandstone ashlar, best seen in the impressive battered base of the curtain wall forming the northern side of the hall. The hall was at first floor level above an undercroft at western end of the block. It survives to a height of 6 to 7m above the court, to the top of the pointed relieving arches of two tall windows, both reduced to a single precarious course of masonry and missing all of their dressed stone. The wall between them has largely collapsed at this level and may originally have contained a fireplace. The polygonal W tower has largely been reduced to a substantial mound of rubble that must encase most of its lower storey, and the a fragment of a polygonal or rectangular stair turret to the east, the toothing of which survives on the face of the curtain wall. The external walls of this tower still stood at least two storeys higher when recorded by artists in the 19th century and contained comfortable chambers and windows with seats on both upper floors. A huge articulated section of its northern appears to lie where it has fallen into the pond to the north and is likely to retain intact structural details. The western tower was also polygonal internally and although almost all of its outer facings have been lost was likely to have had a similar external trace. It may have been entered via a door and short passage in the thickness of the curtain wall a few metres to the east, the bases of which survive. The ground or first floor room is features but retains its wall facings to a height of 2 or 3m; the wall heads are at least 5m above external ground level. There are signs of a very ruined turret extending W along the curtain wall to mirror that of the W tower and a large rectangular latrine turret projecting N along the lost E curtain wall. This retains a monumental outlet arch of a scale equal to that for the Great Gatehouse latrine at nearby Llangibby and which would have enabled a cart to be backed in for cleaning it out. This leads to a huge and high L-shaped cess pit with a bipartite vaulted roof into which four shafts discharged, indicating at least two storeys above the present. The northern ranges of the courtyard seems to have been less substantially constructed and have largely been reduced to mounds of collapsed masonry, but were evidently enclosed by a curtain wall and contained several other rectangular buildings. There are no signs of a gatehouse or other towers.

The monument is of national importance as a closely dated and well preserved caste of the early fourteenth century date high potential to enhance our knowledge of medieval domestic and defensive architecture. In spite of its military trappings it was effectively a fortified hunting lodge on the northern edge of Wentwood Forest serving Roger Bigod’s set at Chepstow. Its massive corner towers and curtain walls contrast with significant weaknesses presented by the lack of serious defences for the remainder of the site, the huge latrine outlet to the eastern tower and large hall windows. It shares group value with a serious of other palatial high status castle buildings constructed throughout Wales and the Marches by the Crown and Marcher Lords at the end of the final Edwardian Conquest, nearby examples including Roger Bigod’s hall, solar and Marten’s Tower at Chepstow and Gilbert de Clare’s nearby Llangibby. These. These were deliberately designed as statements of rank, wealth and lordship and provided lavish, often occasional accommodation for their lords and entourages, enclosed in imposing defences dressed in the latest architectural forms and motifs. Cas Troggy is likely to retain extensive intact buried structural remains and associated archaeological deposits that will provide evidence of its construction, development and use. It is of particular interest due to its probable limited period of use and function as a hunting seat and holds high potential to retain closely dated artefactual and environmental evidence that may enhance our knowledge of regional material culture and of medieval hunting and feasting. Cas Troggy is a well-preserved an important relic of the broader medieval landscape and shares group value with the more modest surviving castles and manors that exploited Wentwood Forest.

The scheduled area comprises the remains described and areas around them within which related evidence may be expected to survive.

Source: Cadw

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