Details

The monument includes the buried and earthwork remains of Offa's Dyke on
St Briavels Common, immediately west of the house known as The Fields.
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 quarry pits to
the east. The bank is between 6m and 8m wide and stands to a maximum height of
1m on its western face and 0.7m on its eastern face. The quarries cover an
area up to 5m wide and 1.5m deep. Part of the northern section of the Dyke is
occupied by the property known as Beech Cottage which was built in the 17th
century. In 1993 an extension was added to the property, and archaeological
excavation showed that the building platform had destroyed all traces of the
bank. It is, however, believed that the quarries will have been preserved as
buried features beneath the platform.
All wooden fence posts, gate posts, stone walls and driveways, Beech Cottage
and all buildings associated with it 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.

Source: Historic England

Reasons for Scheduling

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 west of The Fields survives well.
The bank will have preserved part of the original ground surface,
predating the construction of the monument and, along with the 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.

Source: Historic England

Sources

Books and journals
Catchpole, T, Archaeological Recording at Offa's Dyke, Beeches Bungalow, (1993)
Fox, C, Offa's Dyke, (1955)
Hoyle, J, Vallender, J, Offa's Dyke in Gloucestershire: Management Survay, (1997)

Source: Historic England