The Glamorgan-Gwent Archaeological Trust
Historic Environment Record

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Primary Reference Number (PRN) : 02260.0m
Trust : Glamorgan Gwent
Community : Merthyr Mawr
Unitary authority : Bridgend
NGR : ST8886777527
Site Type (preferred type first) : Early Medieval Dyke
Status : Scheduled Monument

Summary :
Vervil Dyke consists of a bank and a ditch originally measuring 16m in overall width , with the ditch 1.5 to 2.1m deep, the bank 1.2m height and a berm separating the two structures. Cropmarks suggest it was spanned by a second bank and ditch.

Description :
Substantial bank (E) and ditch (W), cutting off E end of salient between Ewenny and Ogmore rivers and running along part of parish boundary between Merthyr Mawr and Coity at point at which it diverges from River Ogmore. Rampart c 16m wide, surviving in one place to height of 1.2m; separted by berm of 0.9m from ditch originally 1.5-2.1m deep. Identified with 'cruc' (=bank) mentioned in early description of Merthyr Mawr. No finds made during excavation.
Crop mark noted parallel with dyke and 700m from it to E; interpreted as second bank and ditch and draws comparisons with c 4ha enclosure thus made of promentary with IA/RB enclosures of area. This second earthwork has now been given the PRN 02483m
Note however that all known examples of these do not depend on topographical features to form their boundaries.

Vervil Dyke is located on the S.E boundary of the parish of Merthyr Mawr, cutting off the east end of a salient between River Ogmore and Ewenny River.
It is made of a bank and a ditch.The fourth OS edition map (1941) show the complete rampart and a description fom 1937 recorded the overall width of the rampart about 16m, with a ditch originally 1.5 to 2.1m deep and a berm separating the two structures (Grimes and H.J. Randall 1945 in RCAHM 1976). The bank was much ploughed down but survived in one place to a height of 1.2m. There was no revetment of timberwork (Grimes and H.J. Randall 1945 in RCAHM 1976).
The cropmarks suggest that the rampart was spanned by a second bank and ditch (prn 02483m), at the point where the two rivers diverge (Vyner 1977). It is probable that the site may be a defended enclosure of about 4 hectares where full use has been made of the natural defences of the flanking rivers (OS 495).
The dyke is near to the Early Christian site of Merthy Mawr and is probably of early medieval date and is probably associated with a major Welsh early Christian site (CADW 1994)

Sources :
Evans, E M , 2001 , Romano-British southeast Wales settlement survey: Final report ( © GGAT)
02/pm desc text//Vyner B/1977/BBCS/328-9
01/pm desc text/RCAHM//1976/Invent I 3/n0807
03/Cadw/1994/full management report

Events :
E003288 : Excavation of Vervil earthwork, Merthyr Mawr (year : 1974-76)
E003289 : Excavation of Vervil earthworks, Merthyr Mawr (year : 1937)
E001657 : Romano-British Southeast Wales Settlement Survey (year : 1998-2001)

Related PRNs : 94715

Compiled date : 08-12-1992

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