Details

The monument includes a 230m long section of a prehistoric boundary known
as the Hertfordshire Grim's Ditch, running broadly north west to south
east, to the east of Hamberlins Lane.
This section of the Grim's Ditch, in Hamberlins Wood, survives as a
clearly visible bank and ditch along most of its length. The earthen bank
measures up to 10m wide and stands up to 1.2m high in some places. To the
south of the bank lies a parallel ditch, approximately 10m wide and up to
1.1m deep. An excavation across a section of Grim's Ditch, approximately
3.5km to the west, 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 survive as buried features along
this section of Grim's Ditch.
A further excavation was carried out in 1991 across a section of Grim's
Ditch, immediately to the east of Hamberlins Wood. This revealed a ditch
measuring up to 1.8m in depth with a steep V-shaped profile and a ploughed
out bank which spread for almost 15m. The basal fill of the ditch produced
pottery which was given an Iron Age date, and the bank was seen to seal
several small shallow features relating to earlier land use.
Further sections of Grim's Ditch exist to the west, south of Smart's Wood,
and about 1.4km to the east, east of Bell Lane. These sections and others
along the entire known route of the boundary are the subject of separate
schedulings.
All fences 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.

Source: Historic England

Reasons for Scheduling

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 edge 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 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. This section of Grim's Ditch in Hamberlins Wood survives well
as a visible earthwork along most of its length and provides a fascinating
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 artefacts or scientific dating material from which to determine
the period of its construction and the duration of its maintenance as an
active boundary.

Source: Historic England

Sources

Books and journals
Network Archaeology, , Grim's Ditch: Archaeological and Management Survey Phase III, (1999)
McDonald, T, 'Chiltern Archaeology:Recent Work. A Handbook for the Next Decade' in The A41 By-Pass Project, Hertfordshire Archaeological Trust, (), 120-2

Source: Historic England