The Glamorgan-Gwent Archaeological Trust
Historic Environment Record
 

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Twyn y Gaer Hillfort, Cwmyoy

Primary Reference Number (PRN) : 01713g
Trust : Glamorgan Gwent
Community : Crucorney
Unitary authority : Monmouthshire
NGR : SO29402195
Site Type (preferred type first) : Iron Age Hillfort
Status : Scheduled Monument

Summary :
Defended Iron Age settlement with two apparent size contractions identified from a private aerial photograph taken in 1999.

Description :
This stronghold occupies a hill the highest part of which is 1399 feet above sea leve, and 750 feet above a river which flows S within half a mile W, and 800 feet above a stream which flows W by S within half a mile S: the ground also falls on other sides, but on the NNW continues as a ridge on a lower level. The position chosen has a natural protection on all sides, especially on the S.
The work is one of an unusual make being divided into three enclosures.
The entrenchments are not of a powerful build, but are in a fair state of presevation: the ramparts are mostly piles of stones more or less overgrown with grass etc. The ramparts were once higher and the ditches deeper.
Subsoil, Stone. Commands the district, or would so command except that there are a good many trees below: the country is also undulating. (Downman 1912; OS Record Card)

The hillfort is as described above. It is grass and fern covered and contains no visble trace of internal habitations. The average width of the ramparts and of the ditches is 9.0m. The average overall width of the cross banks and ditches is 12.0m. The banks show a strong stone content. The inner banks has deteriorated to a scarp across most of the south and south-west sides. (Edwards 1957; OS Record Card)

Finds from the site to date include La Tene style brooches, querns (saddle and beehive) decorative beads, spindle whorls, flints, crucibles and clay ovens. Also a metal spearhead and a metal pin thought to be a carriage pin. (DRB 1973; OS Record Card)

Defended Iron Age settlement with two apparent size contractions identified from a private aerial photograph taken in 1999. (02)

Situated on a hilltop at the southern end of the Vale of Ewyas, the enclosure occupies a commanding position, with moorland grazing on the steep sloped which fall away on all sides.
The enclosure is oblong in shape with the long axis aligned east-west, the internal area divided into three separate enclosures by two sets of banks and ditches running north-south.
The average width of the ramparts and ditches is 9m an the average overall width of the cross banks and ditches is 12m. The banks show a strong stone content and the interior of the fort is slightly convex, with little sign of any features, although there are a few shallow hollows in the northern area. The passage entrance is located to the east and is approximately 7m wide. Entrance through the cross banks are not quite in line with this eastern entrance, both sitting slightly south of the alignment, but in alignment with each other. The eastern bank has a simple 9m wide entrance, the western, more curved like a passage entrance, curving to the west, and with a 7m wide gap. (Wiggins 2006)

Iron Age hillfort on a prominent crest of the Black Mountains overlooking the Honddu Valley north of Abergavenny. Aerial photograph shows stone and earth built single vallate hillfort commanding the meeting point of four valleys. The hillfort has been reduced in size twice, possibly due to a contraction in population. The two cross earthworks have their ditch and rampart facing uphillto the higher ground. This would appear to have made the village weaker in defence. (Sorrell 2017)

Sources :
, OS Record Card
Cadw , Cadw Scheduled Monument Record
Procter, E. , 2018 , The topographical legacy of the medieval monastery: evolving perceptions and realities of monastic landscapes in the southern Welsh Marches
Savory H.N. , 1950 , List of Hill-Forts and Other Earthworks in Wales: II Monmouthshire , The Bulletin of the Board of Celtic Studies : XIII pt.IV : 231-238
Sorrell. J. , 2017 , Hidden History: Archaeology from the air in South-East Wales
Wiggins, H , 2006 , Prehistoric defended enclosures in Gwent ( © GGAT)
01/PM Note/Probert A/1967/Arch in Wales no15 p8
02/Mm AP Gazeteer/2004 January/Sorrell John/Aerial Archaeological Photographs of Gwent/SMR

Events :
E000303 : TWYN Y GAER, CWMYOY, EXCAVATION, 1967 (year : 1967)
E001550 : Prehistoric defended enclosures Gwent (year : 2006)
E002018 : Field visit Twyn y Gaer, Cwmyoy (year : 1912)
E002019 : Field visit Twyn y Gaer, Cwmyoy (year : 1957)
E002020 : Field visit Twyn y Gaer, Cwmyoy (year : 1954)
E002021 : Field visit Twyn y Gaer, Cwmyoy (year : 1987)
E002022 : Field visit Twyn y Gaer, Cwmyoy (year : 1992)
E002023 : Field visit Twyn y Gaer, Cwmyoy (year : 2001)
E002024 : Field visit Twyn y Gaer, Cwmyoy (year : 2006)
E002025 : Field visit Twyn y Gaer, Cwmyoy (year : 1973)

Related records
National Monuments Record NPRN 300043 http://www.coflein.gov.uk/en/site/300043/details
GGAT Historic Environment Record (HER) 01720g
GGAT Historic Environment Record (HER) 12302g

Compiled date : 03-02-2004


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