Reasons for Designation
Linear boundaries are substantial earthwork features comprising single or
multiple ditches and banks which may extend over distances varying between
less than 1km to over 10km. They survive as earthworks or as linear features
visible as cropmarks on aerial photographs or as a combination of both. The
evidence of excavation and study of associated monuments demonstrate that
their construction spans the millennium from the Middle Bronze Age, although
they may have been reused later.
The scale of many linear boundaries has been taken to indicate that they were
constructed by large social groups and were used to mark important boundaries
in the landscape; their impressive scale displaying the corporate prestige of
their builders. They would have been powerful symbols, often with religious
associations, used to define and order the territorial holdings of those
groups who constructed them. Linear earthworks are of considerable importance
for the analysis of settlement and land use in the Bronze Age; all well-
preserved examples will normally merit statutory protection.
The boundary known as the Buckinghamshire and Hertfordshire Grim's Ditch
includes numerous surviving sections from within three main linear earthworks
aligned along the Chiltern Hills between Bradenham and Berkhamsted and
spanning a total distance of 18km. It does not appear that these principal
sections were ever joined to form a continuous boundary. Current evidence
suggests that the sometimes quite sizeable gaps represent areas which were
formerly forested or in which natural features served to perpetuate a division
of the land. The same pattern has been discerned along the North Oxfordshire
Grim's Ditch, to the west of the Thames. A further comparable linear bondary,
the Moel Ditch, extends to the east across parts of neighbouring Bedfordshire.
For the most part the visible sections of Grim's Ditch in the Chilterns
include a wide single ditch flanked by a bank of upcast earth, which is
always upslope of the ditch. Other features, discovered by limited
excavations, include a turf core within the bank, a berm separating the
bank and ditch (concealed over time by the spread of bank material) and a
trench for a fence or palisade along the outer rim of the ditch.
The Buckinghamshire and Hertfordshire Grim's Ditch is thought to have
served as a territorial boundary, separating, and perhaps enclosing,
organised groups of land and settlement. It may also have been an
agricultural boundary, denoting grazing areas and impeding the movement
(or theft) of stock. Excavations to date have provided only limited
dating evidence. Pottery recovered from the fill of the ditch indicates
that it was in existence in the Iron Age. As such, the boundary provides
important evidence for the management of the landscape in the centuries
preceding the Roman Conquest in AD 43, although it may have a considerably
earlier origin. It remained a notable feature in later centuries,
acquiring its name (a variation on the name of the god, Odin) at some
point in the early medieval period, perhaps during the period of pagan
Saxon settlement in the 5th and 6th centuries. The earliest recorded use
of the term, `Grim's Ditch' occurs in a charter granted by Edward, Earl of
Cornwall, in 1291.
All sections of the Buckinghamshire and Hertfordshire Grim's Ditch which
survive in visible form or as well-preserved buried remains (identified by
aerial photography or ground survey) are considered integral to a general
understanding of the monument and will normally merit statutory protection.
The north eastern of the two sections of Grim's Ditch between Oaken Grove
and Lanes End survives well as a visible earthwork along most of its
length. The southernmost section is not clearly visible as an earthwork
but it is known to survive as a buried feature. Both sections provide a
fascinating insight into the nature of early territorial land division in
the Chiltern Hills. They will contain archaeological evidence for the
manner of their construction as well as environmental evidence for the
appearance of the landscape in which the monument was built. The
archaeological evidence may also include artefacts or scientific dating
material from which to determine the period of its construction and the
duration of its maintenance as an active boundary. The stretch of Grim's
Ditch between Wendover and Berkhamstead follows an arc across high ground
above the Aylesbury Vale and Bulbourne Valley. Prehistoric hillforts are
located close by on Boddington Hill on the north west side of Grim's Ditch
and at Cholesbury on the south side.
Details
The monument includes two sections of a prehistoric boundary known as the
Buckinghamshire Grim's Ditch, situated approximately 80m apart, extending
broadly south west from Lanes End towards Oaken Grove.
These sections of Grim's Ditch are situated on ground which slopes to the
south west. The north eastern length survives as a clearly visible
earthwork approximately 90m in length. The earthen bank measures up to
7.2m wide and 1m high in some places. To the south east of the bank lies a
parallel ditch, which has been partially filled in and measures
approximately 8m wide and up to 0.5m in depth. The south western length of
Grim's Ditch to the north east of Oaken Grove measures about 318m in
length and can be traced from the low surviving remains of the bank. The
flanking ditch is now completely infilled, but survives as a buried
feature visible from the air as a cropmark caused by a variation in the
moisture content of the soil. An excavation carried out in 1973 along a
section of Grim's Ditch 1.5km to the north east produced evidence of a
level area, or berm separating the bank and ditch. Evidence for a palisade
trench, which would have supported a wooden fence was also found along the
outer edge of the ditch. Similar components may survive as buried features
along these sections of Grim's Ditch.
At the eastern end of the north eastern length of the monument, where it is
sited in the garden of Jadewood, a garage has truncated part of the ditch and
a large pond has cut into the bank. A section of the ditch is also partially
overlain by the driveway.
The boundary originally continued along the 80m length between these two
sections, however later disturbance in this area appears to have removed
evidence of the monument. Further sections of Grim's Ditch remain visible
to the south west in Oaken Grove and to the north east near Coppice Farm.
These sections and others along the entire known route of the boundary are
the subject of separate schedulings.
The garage, pond and surface of the driveway, together with all the fences,
walls, gates, the greenhouse, oil tank and beehives are excluded from the
scheduling, although the ground beneath them is included.
MAP EXTRACT
The site of the monument is shown on the attached map extract.
It includes a 2 metre boundary around the archaeological features,
considered to be essential for the monument's support and preservation.
