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 on Madgett Hill, 580m west of The Old Mill,
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 section of ditch to the west and 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.
Details
The monument includes the buried and earthwork remains of Offa's Dyke on
Madgett Hill, 580m west of The Old Mill. The majority of this section of
the 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 quarry pits 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.
In this 365m long section the Dyke is visible as a bank with a stretch of
ditch to the west and shallow quarry pits to the east. The bank runs
north-south up the slope of Madgett Hill, before turning to the south west at
the top of the slope to follow the crest of the hill, making use of the
topography of the area. The bank is between 8m and 10m wide at its base and
stands to a maximum height of 1m. To the west of the bank, where it ascends
the face of Madgett Hill, is a ditch which is no longer visible at ground
level, having become infilled over time, but which survives as a buried
feature about 4m wide. After the bank turns south west at the crest of the
hill, the use of natural topography would have reduced the need for a ditch,
and there is no evidence for the existence of one beyond this point. Quarry
ditches are visible on the eastern and south eastern side of the bank along
the entire length of the section, surviving to a maximum depth of 1m and to a
width of between 6m and 16m.
All fence posts, footpath marker posts 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.
