Offa's Dyke: section 90m east of Ty Gwyn

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 east of Ty Gwyn survives well and will retain evidence of its construction and use over time, providing insight into the technical skill of the people who built it. In addition, environmental evidence in the form of pollen and seeds will survive on the buried ground surface beneath the bank and in the ditch. This evidence will provide information about 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 east of Ty Gwyn. 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 740m from the road junction 350m north of Ty Gwyn to the edge of the workings of Llynclys Quarry. At the northernmost end of this section the Dyke has been reduced by the construction of the road, but will survive as a buried feature. Beyond this, the Dyke runs downslope and across the head of a small dry valley as far as Blodwel Bank road. Here the Dyke is visible as a well-defined bank, up to 2.5m high, with a ditch and a slight counterscarp bank in the central section. To the south of Blowdel Bank road the Dyke is visible as a bank which takes the form of a commanding scarp. In the garden of Bryn Offa, the ditch has become infilled, but will survive as a buried feature and is included in the scheduling. In the southern part of this section, the Dyke changes its profile to take account of the steep slope of the flank of the hill at this point. Here the bank is up to 1m high on its eastern side. To the west, the bank falls away steeply into the ditch, which has become largely infilled by landslip. A pronounced counterscarp bank is visible to the west of the ditch. A series of small quarry pits on the east of the bank provided further material for the bank's construction. These are visible as a series of shallow hollows up to 10m from the base of the bank itself. The quarry pits have been partly obscured by later ridge and furrow cultivation. Further sections of Offa's Dyke 20m to the north and across the valley beyond the quarries at Llynclys and the village of Porth-y-waen are the subject of separate schedulings. All fence posts, telegraph poles, road surfaces, and the garden rockeries and furniture of Bryn Offa are excluded from the scheduling, although the ground beneath these features 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:

32610

Legacy System:

RSM

Sources

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

End of official list entry

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