The Glamorgan-Gwent Archaeological Trust
Historic Environment Record

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Bwlch yr Afan

Primary Reference Number (PRN) : 02265.0m
Trust : Glamorgan Gwent
Community : Ogmore Valley
Unitary authority : Bridgend
NGR : SS91969510
Site Type (preferred type first) : Early Medieval Dyke
Status : Scheduled Monument

Summary :
Dyke runs for 192m, W.S.W to E.S.E. In two sections, the west is c.90m long. It is unusual, comprising two banks of equal size flanking a central ditch, with an overall width of about 10.7m by 1m high. The central ditch is c.1m wide and 1m in depth.

Description :
Bwlch Yr Afan is situated on a narrow ridge at c.520m OD between the summits of Werfa to the southwest and Twyn Crugyrafan to the north. Crossing a saddle at about 520m above OD, the dyke runs almost straight for 192m, W.S.W to E.S.E. Its W. end coincides with the line of an old trackway, but does not reach any natural obstacle. Its E. end dies away in a patch of marsh. The dyke is unusual in that it comprises two banks of equal size flanking a central ditch, with an overall width of about 10.7m by 1m high. The dyke is best-preserved to the west section (where its length is c.90m), where the twin banks stand to up 1.5m in height and over 3m wide. The central ditch is c.1m wide and 1m in depth . The western end of the dyke gradually fades out into the steep slope of Cwm Nant-ty and the northern bank and ditch becomes obscured at the line of the modern field boundary to the east. There is no stonework in the structure. Examination by C.B Crampton (1966) showed that the dyke was made not long after the Ericaceae pollen reached its maximum, what implies that a heathland existed before the dyke was constructed and that this dyke may indeed post date the construction of Bwlchgarw 2 km to the west (R. LEWIS 2006 ; RCAHMW 1976) .

Sources :
RCAHMW , 1976 , An inventory of the Ancient monuments in Glamorgan, I, iii: The Early Christian period
02/PM List/Cadw/1991/AM107
01/PM Desc Text/RCAHMW/1976/Glam Invent volI pt3/no809
R. LEWIS, 2006, Cross Ridge Dykes of Southeast Wales : Survey and Excavation
Crampton, CB, 1966, An interpretation of the pollen and soils in Cross-Ridge Dykes of Glamorgan, BBC XXI, pt IV.

Events :
E002524 : Llangeinor Parish DBA (year : 2011)
E005433 : Cross Ridge Dykes of Southeast Wales (year : 2006)

Related PRNs : 94624

Compiled date : 13-08-1992

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