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 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 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 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 parcels of land and settlement. It may also have been used as 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
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
setlement 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 Shire Lane and Kiln Road
survives well as a visible earthwork along most of its length and provides
a fascinating insight into the nature of 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 artefacts or scientific dating material from which to determine
the period of construction and the duration of its maintenance as an
active boundary. The section is part of a larger stretch of Grim's Ditch
between Wendover and Berkhamstead which follows an arc across high ground
above the Aylesbury Vale and Bulbourne Valley following a similar course
to the modern Ridgeway path less than one kilometre to the north west,
which is itself a reflection of a prehistoric route along the line of the
Chiltern Hills. Prehistoric hillforts are located close by on Boddington
Hill, 3.5km to the south west and Cholesbury Hillfort 2km to the south.
Details
The monument includes a 1150m length of a prehistoric boundary known as
the Hertfordshire Grim's Ditch, running broadly west to east from
Longcroft Farm on Shire Lane to Kiln Road, crossing Browns Lane at a point
some 500m south of Hastoe Farm.
This section of the Grim's Ditch, survives as a clearly visible bank and
ditch along most of its length. The earthen bank measures up to 13m wide
and stands up to 1.3m high in some places. To the south of the bank lies a
parallel ditch, approximately 12m wide and up to 0.75m in depth. At the
western end of this section of the monument and immediately to the east of
Browns Lane the ditch has been levelled by the construction of a driveway
and by cultivation, respectively, but will survive as a buried feature. An
excavation along this section of Grim's Ditch, approximately 270m to the
west of Kiln Road, carried out in 1973, 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 also survive as buried features
along the whole of this section of Grim's Ditch.
Further sections of Grim's Ditch exist to the west, immediately west of
Shire Lane and to the east, to the east of Kiln Lane. These sections and
others along the entire known route of the boundary are the subject of
separate schedulings.
The concrete driveway to Longcroft Farmhouse and the surface of Browns
Lane, together with all fences, gates and stiles, and modern structures
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.
It includes a 2 metre boundary around the archaeological features,
considered to be essential for the monument's support and preservation.
