Details

The monument includes the main compound of Fort Farningham London mobilisation
centre, and a later, Royal Observer Corps underground Monitoring Post. It is
situated on high ground above the River Darent, around 1.5km west of
Farningham.
The north east-south west aligned, roughly semi-circular compound, is defined
on its south eastern front by a large, crescent shaped earthen rampart. The
surrounding ditch was infilled during the second half of the 20th century, and
partly damaged on its south western side by construction of a house, but will
survive for much of its length as a buried feature, around 20m in width. The
ditch contained spiked railings, known as a Dacoit fence, which extended to
the rear, or gorge, of the centre, completely enclosing the compound.
The north west facing gorge contains a sunken roadway which is approached from
the main access road by a vehicle ramp at its northern end, and was made
defensible by a row of three, slightly projecting casemates, with the rear
facing doors and windows still retaining their loopholed, metal shutters.
Flanking concrete walls extend to meet the ends of the rampart. Access to the
interior is through a break in the southern gorge wall, protected by stout
metal doors which open onto the southern one of two courtyards flanking the
central casemates. The top of the rampart and gorge wall can be reached by
concrete steps from each courtyard and could therefore act as a musketry
parapet, allowing the mobilisation centre some degree of self-defence in the
event of enemy attack. The surrounding ditch could also be accessed from each
courtyard by way of a tunnel, labelled `covered way', which led out through
the rampart from a casemate at the rear of each courtyard.
The courtyards are linked by a covered passageway which runs through the
central casemates and the three roomed magazine block, which is partly covered
by the earthen rampart, or blast-bank. To minimise the risk of explosion, the
magazine chambers were lit by lamps set in recesses behind panes of glass, and
accessed from the lamp passage which surrounds the magazine. The corridor in
front of the chambers contained a shifting lobby, where magazine personnel
changed into protective and non-spark producing clothes. Many of the original
fittings survive, including the lamp recess casements and some of the original
notices labelling various components of the magazines.
Buried within the north eastern section of the infilled ditch, is an
underground bunker, constructed and used during the 1960s by the Royal
Observer Corps. This Monitoring Post formed part of the UK Warning and
Monitoring Organisation and belonged to a network of such posts, designed to
record the location, height and power of a nuclear explosion and to monitor
radioactive fallout. The surface monitoring devices have been removed,
although above-ground remains include the air ventilator and the top of the
vertical access shaft. The buried chamber, designed to accommodate a crew of
three, is likely to retain many of its original features.
Associated with the main compound are the original, semi-detached pair of
caretakers cottages and the mobilisation tool store, situated on either side
of the north western approach road, outside the perimeter ditch. The cottages
are now occupied as private residences and the tool store has been converted
for business use, and these buildings are therefore not included in the
scheduling. Part of the ditch in the south west has been damaged by past
modern construction of a house and associated landscaping, and this area is
also not included in the scheduling.
In addition to the boiler shed, and associated components, on the south
western edge of the rampart, a number of features within the area of the
monument are excluded from the scheduling, these are: all modern fences and
hedging; the Ordnance Survey trig point and the temporary wooden structure
located on top of the rampart; all modern fixtures and fittings, including
components of the modern electricity systems, as well as modern materials and
equipment stored within the mobilisation centre. The ground beneath these
items is included in the scheduling, together with the structures and surfaces
related to the military use of the site, to which some of these features are
attached.

MAP EXTRACT
The site of the monument is shown on the attached map extract.

Source: Historic England

Reasons for Scheduling

The 15 London mobilisation centres, constructed during the 1890s, formed part
of a comprehensive military scheme known as the London Defence Positions,
drawn up in 1888 to protect the capital in the event of enemy invasion. The
scheme was a response to the rapid progress made in warship production by
France and Russia during the early 1880s, which had led to official doubts
about the Royal Navy's defence capability. Essentially a contingency plan, it
provided for the establishment of a 72 mile long, entrenched stop-line divided
into ten tactical sectors and supported by artillery batteries and redoubts.
The planned stop-line ran from the southern edge of the Surrey and Kent Downs,
up the western side of the Darenth Valley to the Thames, and then north
westwards through Essex from Tilbury Fort to Epping. Although the stop-line
and main defence positions were not to be established until an invasion was
imminent, it was thought prudent to build a series of mobilisation centres, 13
on new sites, along the projected course, either for artillery deployment or
where troops could assemble and collect tools and supplies. By 1905, official
confidence in the Royal Navy had been restored, and the now obsolete
mobilisation centres were abandoned and gradually sold off.
No two mobilisation centres are exactly alike, and a broad distinction can be
drawn between the four centres purpose built for artillery deployment, and
eight which functioned as infantry positions. However, in general terms there
are close similarities: each, for example, was typically enclosed by a
rampart, ditch and spiked fence, containing a partly earth-sheltered,
reinforced concrete and brick built magazine and stores. Beyond the main
compound were associated buildings of a standard type, including a brick
caretakers lodge and a large, barn-like tool store. Most mobilisation centres
have been the subject of subsequent alteration and/or reuse. As a short-lived
and rare monument type, all mobilisation centres with surviving remains
sufficient to give a clear impression of their original form and function are
considered to be nationally important.

Unusually for this type of monument, Fort Farningham has remained largely free
of alteration or renovation and, despite the infilling of the ditch, survives
comparatively well and will retain evidence relating to the construction and
use of mobilisation centres, including the tunnels beneath the rampart which
are unique to Fort Farningham. The construction of an Royal Observer Corps
nuclear Monitoring Post within the perimeter ditch, illustrates the renewed
significance of this location during the Cold War period.

Source: Historic England

Sources

Books and journals
War Office, , Fort Farningham design plan, (1899)
Wood, D, Attack Warning Red. The ROC and the defence of Britain 1925-1992, (1992)
Beanse, A, Gill, RJ, 'The Redan (Palmerston Forts Society)' in The London Mobilisation Centres, , Vol. 43, (1998), 12-24
Smith, V, 'Post-Medieval Archaeology' in Chatham and London: The Changing Face of English Land Fortification 1870-1918, , Vol. 19, (1985), 105-149
Other
Beanse, A and Gill, RJ, Farningham Mobilisation Centre, 1998,
Beanse, A and Smith, VTC, Re: Discussion of outer earthworks shown on 1899 design plan, (1999)
Smith, V, (1999)

Source: Historic England