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The Bulwark: a Civil War fieldwork and World War II gun emplacement, 150m north of Earith Bridge

A Scheduled Monument in Haddenham, Cambridgeshire

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Latitude: 52.3552 / 52°21'18"N

Longitude: 0.0433 / 0°2'35"E

OS Eastings: 539252.507659

OS Northings: 274979.005095

OS Grid: TL392749

Mapcode National: GBR L5F.CRR

Mapcode Global: VHHJG.P2RB

Entry Name: The Bulwark: a Civil War fieldwork and World War II gun emplacement, 150m north of Earith Bridge

Scheduled Date: 18 January 1926

Last Amended: 27 September 1995

Source: Historic England

Source ID: 1013282

English Heritage Legacy ID: 27105

County: Cambridgeshire

Civil Parish: Haddenham

Traditional County: Huntingdonshire

Lieutenancy Area (Ceremonial County): Cambridgeshire

Church of England Parish: Bluntisham cum Earith St Mary

Church of England Diocese: Ely


The Civil War fieldwork known as The Bulwark is situated to the east of
Earith, within a narrow strip of land (the Hundred Foot Washes) which
separates the Old and New Bedford Rivers, both of which join the Great River
Ouse some 150m to the south.

The Bulwark was strategically placed to command an important river crossing at
the western end of the fen causeway which linked Huntingdon to the the Isle of
Ely; and to control traffic on both the River Great Ouse, and the earlier of
the two artificial navigations (the Old Bedford River), constructed by the
engineer Vermuyden in the 1630's. The monument includes the fieldwork with its
square inner enclosure, corner bastions, perimeter defences and outworks; and
a small steel-domed gun emplacement positioned within the earlier
fortifications during World War II.

The central enclosure is raised about 0.7m above the surrounding ground level,
measures approximately 60m square, and is located within the angle between the
the River Great Ouse and the Old Bedford River which lies c.300m to the south
west. The enclosure is surrounded by an earthen rampart and parapet, which
varies between 0.5m and 1m in height, and between 4m and 10m in width. The
parapet would originally have had a near vertical inner face supported by
timber work and pierced by gun loops, but has since subsided to a rounded
profile. It continues around each of the four, lozenge-shaped bastions which
form diagonal projections at the north, south, east and west corners, with a
single gap or entrance in the centre of the south east side. The bastions each
extend for about 30m and measure approximately 20m across the widest parts.
These served as cavaliers (artillery platforms) with a wide range of fire,
and allowed close quarter defence for the ramparts to either side. This
central stronghold, or sconce, is surrounded by a broad ditch with steep sides
and a flat base. This measures about 17m in width, descending to about 3m
below the parapet, and may originally have been strengthened by a fringe of
sharpened poles inserted in the inner face. Sample excavation across the
northern bastion in 1906 demonstrated that the profile of the inner
fortifications resulted from a single phase of construction, with the upcast
gravels forming the inner rampart, clad with heavy clay from the base of the
ditch. The 1906 excavation also revealed a shallow deposit of dark alluvial
silts in the bottom of the ditch which indicate that when freshly cut it
contained standing water. The ditch is flanked by an outer bank rising in two
stages, the outer stage forming a further parapet or breastwork, with a
rifle platform or covered way behind. The bank is generally 6m-8m wide and
1m high, with the breastwork covering about half its width and raising its
height by approximately 0.8m. The breastwork is also thought to have subsided
since the collapse or removal of an inner palisade, but even in its original
condition, it would have been lower than the firing height from the parapet
within the sconce. The covered way provided access to two bastions in the
outer defensive circuit, located in the centre of the north eastern and south
eastern arms. The former is a roughly triangular protrusion extending for c.6m
beyond the line of the bank. The latter is similar in size but with a more
rounded appearance. Both have narrow gaps, or sally ports, in the breastwork;
and square platforms behind, providing mustering points or further gun
emplacements. The north eastern platform is linked to the central enclosure by
two narrow causeways across the ditch. The south eastern platform is
approached by a square projection from the inner parapet which extends about
half way across the ditch, thought to indicate the position of a short
drawbridge. Except on these bastions, the outer face of the breastwork forms
part of a single slope (or glacis), with an unrestricted field of fire,
leading into the inner scarp of an external ditch. This ditch is generally 3m
in width and c.0.7m deep, having been partially infilled by silts deposited
during the seasonal flooding of the washes. It remains visible around the full
circuit of the fortifications except at the tip of the southern corner bastion
where the earthworks have been reduced and the ditch largely infilled. Along
the north eastern arm it has been partially recut by a later field drain.
On the north western side of the fort, the perimeter ditch extends to form a
rectangular enclosure which projects for about 100m towards the Old Bedford
River, providing a fortified approach or outwork. The outwork measures
approximately 40m in width (the same width as the inner parapet between the
corner bastions), and has indications of two further lozenge-shaped cavaliers
at the far corners. Slight traces of an extension to the outer breastwork
extend down each side of the outwork leaving a gap at the approach to the
sconce, where a large, squared projection from the outer bank into the main
ditch is thought to represent the footings for a drawbridge. A similar outwork
extends from the south west side of the fort, continuing for about 150m
towards the road on the north bank of the River Great Ouse. This also is
accompanied by a gap in the breastwork and a square bridgehead on the outer
bank of the inner ditch. Two major entrances to a fortification of this type
is an extremely unusual arrangement, perhaps explained by the garrison's
reliance on reinforcements and supplies by both road and river.

The Bulwark was constructed by Parliamentarian forces between 1643 and 1645,
during the first stage of the Civil War. It is believed to be the work of two
English engineers, Richard Clamp and Captain John Hopes, although the design
is largely based on the Dutch school of military fortification, then dominant
on the continent. The precise date of construction is unknown. At the onset of
the war Huntingdonshire formed part of the Midlands Association of
Parliamentarian counties, becoming a frontier county of the Eastern
Association shortly after it was formed in 1643. The Eastern Association led
by Oliver Cromwell (amongst others) initially took a defensive stance,
concentrating on the fortification of Cambridge and the control of major
communication routes which, in the fens, largely consisted of the principal
causeways and navigations. The Bulwark is unlikely to have been constructed
prior to this period since, in the previous year when the Queen's troops and
forces under the Marquis of Newcastle threatened the area, an officer named
Tyrell Jocelyn reported that the bridge at Earith (Hermitage Pass) could be
held for a week; an extremely low estimate if the fortifications were in
place. Early in 1643 Cromwell embarked on a strategy to consolidate the
Association's military frontier; first securing the Royalist ports of
Lowestoft and King's Lynn, then moving on to take Peterborough and finally
Crowland, the last Royalist outpost in the fens. In May, there was a Royalist
rebellion on the Isle of Ely, which was eventually suppressed by troops from
Cambridge. However, this rebellion demonstrated that the Isle would be readily
defendable by a larger force should it fall to the opposition. The major
approaches from the north and west were therefore strengthened, with garrisons
at Wisbech and Earith, perhaps involving the construction of the Bulwark, and
possibly also the large pentagonal sconce at Horsey Hill, near Peterborough.
If these fortifications were not erected in response to this crisis, they may
well have been built in the following year after the Parliamentarian defeat at
Cropredy Bridge, near Banbury, when the Association was ordered to take
additional defensive measures. A further defeat at Lostwithiel in Cornwall in
October 1644 resulted in Cromwell marching his forces west, leaving the
eastern counties short of troops. Parliamentarian fortunes improved after the
battle of Naseby in August 1645. However, in retreat from the battle,
Charles I turned south east briefly, taking first Stamford then Huntingdon.
Although this occupation was short lived the aftermath saw renewed
fortification of all the Ouse crossings, and was perhaps the last occasion on
which the Bulwark might have been built.

As far as the fens were concerned this was the end of the first phase of the
war, the Bulwark, like many other East Anglian fortifications, never having
seen action. The second phase saw far less activity locally, the only major
action in the area being a provincial uprising in Colchester in 1648.
The small structure located on the southern, inner bastion is an unusual form
of gun emplacement dating from World War II, known as the `Alan-Williams'
turret. It consists of a rotating steel dome 1.5m in diameter, set over a
concrete lined pit with a entrance passage to the west. The dome contains
space for two men, one to rotate the upper section, the other to operate a
machine gun (since removed). The gun could be mounted through a square
aperture in the side of the dome, or a circular aperture above. It was
intended both for ground defence, covering the embankment of the New Bedford
River, and against aerial attacks aimed at the bridges and sluices to the
south. It is not known if it was ever used in action.
All fences, fence posts and gates are excluded from the scheduling, although
the ground beneath these features is included.

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

English Civil War fieldworks are earthworks which were raised during military
operations between 1642 and 1645 to provide temporary protection for infantry
or to act as gun emplacements. The earthworks, which may have been reinforced
with revetting and palisades, consisted of banks and ditches and varied in
complexity from simple breastworks to complex systems of banks and inter-
connected trenches. They can be recognised today as surviving earthworks or as
crop- or soil-marks on aerial photographs. The circumstances and cost of their
construction may be referred to in contemporary historical documents.
Fieldworks are recorded widely throughout England with concentrations in the
main areas of campaigning. Those with a defensive function were often sited to
protect settlements or their approaches. Those with an offensive function were
designed to dominate defensive positions and to contain the besieged areas.
There are some 150 surviving examples of fieldworks recorded nationally. All
examples which survive well and/or represent particular forms of construction
are identified as nationally important.

The fieldwork near Earith is very well preserved, retaining numerous details
illustrating the style of defence. Only a small part of the earthworks (at the
southern corner of the monument) have been significantly disturbed, and here
the ditch will survive as a buried feature. The banks, parapets and bastions
contain details of their construction, and the ditches contain shallow
deposits of waterlogged silts which both indicate the transient use of the
site, and provide conditions suitable for the preservation of organic and
inorganic artefacts from the period of occupation.

The Bulwark is amongst the most elaborate fortifications in England to have
survived from the Civil War. It demonstrates clear influences of contemporary
continental military design and shows how these ideas were adapted in the
English context. The Earith Bulwark demonstrates the importance of the Earith
crossing during the Civil War as part of the military frontier surrounding the
Isle of Ely and, together with a number of other fortifications in the region
(both in similar rural locations and in the main towns), illustrates the
variety of methods adopted for the defence of the Eastern Association. The
survival of the two rectangular outworks demonstrate the garrison's reliance
on both the adjacent means of communication.

The World War II gun emplacement is also a very well preserved and unusual
survival, retaining the principal elements of its design. The use of the dual
purpose Alan-Williams turret in this location illustrates its twin purposes: a
defence against the threat of German invasion along the Ouse valley, and the
more immediate problems posed by the vulnerability of the Earith flood
defences from the air.

Source: Historic England


Books and journals
Darby, HC, The Changing Fenland, (1983), 76-77
Holmes, C, The Eastern Association in the English Civil War, (1974), 73
Kingston, A, East Anglia and the Great Civil War, (1902)
Morgan, K O (ed), The Oxford History of Britain, (1989), 675
Osborne, M, Cromwellian Fortifications in Cambridgeshire, (1990)
Shirer, W L, The Rise and Fall of the Third Reich, (1969), 914
Wickes, M, A History of Huntingdon, (1985)
Kent, P, 'Fortress' in East Anglian Fortifications in the Twentieth Century, , Vol. 3, (1989), 43-57
Keynes, G L, Evelyn White, H G, 'Proceedings of the Cambridge Antiquarian Society' in Excavations at Earith Bulwarks, , Vol. 12, (1908), 277-61
Saunders, A D, 'Archaeological Journal' in Proceedings, , Vol. 124, (1967), 222-3
report on gun emplacement (SMR 1780a), Wyatt, G, Earith Bulwark, (1980)
Text and plans, RCHM(E), Inventory of Historic Monuments, Huntingdonshire, (1926)
Undated, lecture notes (Cambs SMR), Baggs, T, The Civil War in East Anglia, (1980)

Source: Historic England

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