Offa's Dyke: section immediately north west of Coxbury Farm

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 immediately north west of Coxbury Farm survives well. The bank will have preserved part of the original ground surface predating the construction of the monument and, along with the ditch and counterscarp bank to the west and quarries to the east, will contain environmental evidence in the form of organic remains which will relate both to the Dyke and to the landscape within which it was constructed. The bank will also contain evidence relating to the methods of construction of the monument and the building materials used.

Details

The monument includes the buried and earthwork remains of Offa's Dyke immediately north west of Coxbury Farm. Offa's Dyke generally consists of a bank up to 3.5m high with an intermittent ditch to the west and quarry ditches to the east. In places Offa's Dyke was strengthened by additional earthworks, namely a berm between the bank and ditch, and a counterscarp bank on the western lip of the ditch. This 514m long section of the Dyke is visible as a bank, with a ditch and a short section of counterscarp bank to the west and quarry pits to the east. The bank is between 8m and 10m wide at its base and stands to a maximum height of 1.7m on its outer face and 0.6m on its inner face. The ditch is up to 5m wide and 1m deep, but is only visible at the northern end of the section. To the south the ditch has become infilled over time, but will survive as a buried feature approximately 5m wide. The counterscarp bank is also only visible at the northern end of the section, and is between 4m and 8m wide and stands to a maximum height of 0.8m. The quarry pits to the east of the bank form a broad band 3m to 6m wide and up to 1m deep. In the centre of the section, the Dyke survives as a terrace 1m high following the line of the present field boundary. All wooden fence posts, signposts, gates and stiles 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:

33454

Legacy System:

RSM

Sources

Books and journals
Hoyle, J, Vallender, J, Offa's Dyke in Gloucestershire: Management Survay, (1997), 74

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