Offa's Dyke: section 90m south of Brynorgan

Reasons for Designation

Offa's Dyke is the longest linear earthwork in Britain, approximately 220km, running from Treuddyn, near Mold, to Sedbury on the Severn estuary. It was constructed towards the end of the eighth century AD by the Mercian king Offa, and is believed to have formed a long-lived territorial, and possibly defensive, boundary between the Saxon kingdom of Mercia and the Welsh kingdoms. The Dyke is not continuous and consists of a number of discrete lengths separated by gaps of up to 23km. It is clear from the nature of certain sections that differences in the scale and character of adjoining portions were the result of separate gangs being employed on different lengths. Where possible, natural topographic features such as slopes or rivers were utilised, and the form of Offa's Dyke is therefore clearly related to the topography. Along most of its length it consists of a bank with a ditch to the west. Excavation has indicated that at least some lengths of the bank had a vertical outer face of either laid stonework or turf revetment. The ditch generally seems to have been used to provide most of the bank material, although there is also evidence in some locations of shallow quarries. In places, a berm divides the bank and ditch, and a counterscarp bank may be present on the lip of the ditch. Offa's Dyke now survives in various states of preservation in the form of earthworks and, where sections have been levelled and infilled, as buried features. Although some sections of the frontier system no longer survive visibly, sufficient evidence does exist for its position to be accurately identified throughout most of its length. In view of its contribution towards the study of early medieval territorial patterns, all sections of Offa's Dyke exhibiting significant archaeological remains are considered worthy of protection.

The section of Offa's Dyke 90m south of Brynorgan survives well despite some erosion of the remains. It will retain information about its construction and use over time. In addition, environmental evidence such as pollen and seeds within the fills of the ditch and on the buried ground surface below the bank will provide evidence for the landscape in which the monument was constructed.

Details

The monument includes the earthwork and buried remains of a section of the linear boundary known as Offa's Dyke 90m south of Brynorgan. Offa's Dyke generally consists of a bank, up to 3.5m high, with an intermittent parallel ditch and quarry pits in places. It was strengthened in some areas by additional earthworks, namely a berm between the bank and ditch and a counterscarp bank on the outer lip of the ditch. In this section the Dyke runs for 95m from the southern gateway of Brynorgan to a point 140m south of the farmhouse. The northern end is visible as a shallow ditch with a slight bank on its east side. There is little trace of the counterscarp in this section, although it will survive as a buried feature. The overall width of the Dyke here is about 18m. Further sections of Offa's Dyke 40m to the north and 230m to the south are the subject of separate schedulings. All fence posts are excluded from the scheduling, although the ground beneath them is included.

MAP EXTRACT The site of the monument is shown on the attached map extract.

Legacy

The contents of this record have been generated from a legacy data system.

Legacy System number:

32606

Legacy System:

RSM

Sources

Books and journals
Fox, C, Offa's Dyke, (1955), 137
Kay, K, Richards, , Offa's Dyke Path North, (1995), 18

End of official list entry

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