Details

The monument includes the buried and earthwork remains of Offa's Dyke in
Boatwood Plantation, 320m south west of Chase Farm. This section of Offa's
Dyke is in the care of the Secretary of State. Offa's Dyke generally
consists of a bank up to 3.5m high with an intermittent ditch to the west
and quarries 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 lip of the ditch.

This 364m long section of the Dyke turns from its usual alignment to run
north west-south east. It is visible as a bank with a berm on its south
side and contiguous quarry pits to the north. The bank is up to 17m wide
at its base and stands to between 2.5m and 3.5m high on its southern face
and to between 0.8m and 1.8m on its northern face. The berm is about 2m
wide and represents an artificial break in slope at the base of the
earthen bank. The quarries are up to 10m wide and about 1m deep. A stone
boundary wall, which is thought to date from the mid to late 19th
century, runs along the top of the bank throughout the length of this
scheduling. There is a gap in the Dyke at Ordnance Survey NGR ST54929845
formed by the cutting of a forestry access road, material from which was
thrown up to form a bund. It is not thought to represent an original
crossing point through the monument.

The metalled surface of the forestry track, all fence posts, sign posts,
marker posts, telegraph poles and the stone wall which runs along the top of
the bank 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 in Boatwood Plantation, 320m south west of
Chase Farm, survives well, and illustrates the use of natural topography
to enhance the form and visibility of the Dyke. The bank will have
preserved part of the original ground surface, predating the construction
of the monument and, along with the berm to the south and the quarries to
the north, 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
Hoyle, J, Vallender, J, Offa's Dyke in Gloucestershire: Management Survay, (1997)

Source: Historic England