The Glamorgan-Gwent Archaeological Trust
Historic Environment Record

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Primary Reference Number (PRN) : 01664g
Trust : Glamorgan Gwent
Community : Grosmont
Unitary authority : Monmouthshire
NGR : SO40522445
Site Type (preferred type first) : Medieval Castle
Status : listed building I, Scheduled Monument

Summary :
First castle built around 1154, and comprised of a simple wooden palisade and ditch structure (only the moat remains of this earliest period). The castle was constructed in masonary over 3 main stages, from 1210 to 1330.

Description :
First castle on site in existence by 1154, which consisted of wooden buildings defended by a palisade and ditch, but only the moat remains of this earliest period.
The masonry castle was built in 3 main periods. The Great Hall is the earliest structure, dating from about 1210. The second building period, during the first half of the C13th, saw the enclosure of the inner ward, with a stone curtain flanked by 3 semi-circular towers and a projecting gatehouse. The final stage, probably around 1330, included the addition of a range of rooms outside the N curtain and the enlargement and heightening of the SW tower.
The stone castle stands on a roughly rectangluar platform surrounded by a ditch 6m deep. The remains of a probable bailey encircling the castle can be traced on the SE and NE as a scarped slope 4m high, and on the N as 2 banks .3m high and 9m wide with an intermediate ditch 1m deep.

Phillips notes that Groesmont Castle is part of a group of castles (with Skenfrith and White castle), and that key features include a masonry construction on a mound formed by digging a surrounding ditch. The mound was thought to have been artificial but upon clearance the raised centre appears to be tumble from the walls (Phillips 2004).

Sources :
Phillips, N. , 2004 , Thesis: Earthwork Castles of Gwent and Ergyng AD 1050 – 1250
The Handley Partnership , HAAbase built heritage assessment system: Buildings at Risk database
13/PM Desc Text/O'Neil St J/1932/A Syrian Vase found in Monmouthshire/Arch Cam vol LXXXVII pp193-4
12/MM Desc Text/Cadw/1992/AM107
18/PM Survey/Geophysical Surveys (Bradford) for Cadw/1990/Report on Geophysical Survey
17/PM Desc Text/Knight J/1977/Med Castles of Monmouthshire/Gwent Local Hist no42-3 pp34&40
14/PM Desc Text/Rigold SE/1975/Med Arch vol 19 pp48-91
11/PM Map/GGAT/Owen-John H/7.12.88/A84.08
10/MM Desc Text/Cadw/Whittle E/1987/AM107
09/MM Mention/Cadw/1956/Buildings of Special Arch or Hist Interest p4
08/PM Desc Text/Salisbury & Delaney/1975/Monmouth Implications Report/5.2.1.
07/PM Desc Text/1929/Trans Bristol & Glos Arch Soc vol 49 pp26
05/PM Desc Text/Braun H/1936/The English Castle p78
04/PH Desc Text/Clark GT/1884/Med Milit Archit vol II pp51-3
03/PM Desc Text/Bradney JA/1907/Hist of Monmouth vol I pp69-72
02/PH Desc Text/Bagnall-Oakley/1895-7/Trans Bristol & Glos Arch Soc vol XX pp88-92
01/MM Record Card/OS/1972/SO 42 SW 3
16/PM Mention/1979/Report of the Annual Meeting 1978/Arch Camb vol CXXVIII pp178-85
15/PH Desc Text/Ponnfeldt/1889/Trans Card Nat Soc vol XXI pl1 PP37-40
06/PM Desc Text/1935/Ant J vol XV pp326-30

Events :
E003884 : Grosmont Castle (year : 1990)
E004063 : Earthwork Castles of Gwent and Ergyng AD 1050 – 1250 (year : 2004)
E002379 : Myrtle Cottage, Grosmont, Monmouthshire, EVAL (year : 1998)
E002395 : Forge Site Grosmont, Gwent, DBA (supplementary) (year : 1995)

Related PRNs : 93388

Compiled date : 02-12-1988

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