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 re-used 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 feature known as the Buckinghamshire and Hertfordshire Grim's Ditch
includes a series of three prehistoric linear earthworks aligned along the
scarp face of the Chiltern Hills between Bradenham and Berkhamstead, together
spanning a distance of some 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, a separate monument to the west of the River Thames. A further
comparable linear boundary, 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 on the south side by a bank of upcast
earth overlying a turf core. Excavations carried out in 1973 and 1991 in the
parishes of Tring and Northchurch in Hertfordshire identified a berm between
the bank and ditch, over which the bank later spread. In one excavation a
narrow trench, possibly dug to support a palisade or fence, was discovered
along the edge of the ditch furthest from the bank.
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 that it was in existence
in the Iron Age, although it may have a considerably earlier origin. As such,
the boundary provides important evidence for the management of the landscape
in the centuries preceding the Roman Conquest in AD 43. It remained a notable
feature in later centuries, acquiring its present 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 section of Grim's Ditch between a point west of White House Farm and Lily
Bank Farm survives well as a visible earthwork along most of its length and
provides a valuable insight into the nature of early territorial land division
in the Chiltern Hills. It will contain archaeological evidence for the manner
of its construction as well as environmental evidence for the appearance of
the landscape in which it was built. The archaeological evidence may also
include either artefacts or scientific dating material from which to determine
the period of its construction and the duration of its maintenance as an
active boundary.
Details
The monument includes a 1.02km long section of a prehistoric linear boundary
known as the Buckinghamshire Grim's Ditch running broadly south west to north
east from a point west of White House Farm towards Lily Bank Farm. It is
situated on a ridge of high ground which falls away at either end of this
section of Grim's Ditch.
The Buckinghamshire Grim's Ditch survives as a clearly visible bank and ditch
along all but the central section of this length. Here the ditch survives but
the bank is intermittent, having been partially levelled by cultivation over
the years. At the south west and north east ends of this section, the
earthwork has been cut away by later extraction pits.
The section of Grim's Ditch includes a ditch, up to 8m wide, which has been
partially infilled over the years and now has a maximum depth of 1.2m. The
surviving sections of parallel bank, on the north west side of the ditch,
measure up to 5m wide and 0.5m in height. Excavations along other sections of
Grim's Ditch in Hertfordshire, carried out in 1973 and 1991, 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. These components are thought to survive
as buried features along this section of Grim's Ditch.
The ditch was subsequently adopted as a trackway between Lacey Green and
Parslow's Hillock. It has been in use as a bridlepath since at least 1823 when
it was marked as such on the Princes Risborough Enclosure map.
All fences, gates and stiles 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.
