Box Hill Fort: a London mobilisation centre

Reasons for Designation

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.

Despite some modern consolidation and repair, the London mobilisation centre on Box Hill survives comparatively well, retaining much evidence for the construction and original use of the monument.

Details

The monument includes the main compound of Box Hill London mobilisation centre, situated on a chalk ridge of the Surrey Downs around 2km north east of Dorking. The north west-south east aligned compound survives as a north east facing, reinforced concrete and brick structure housing magazines and stores. The flat-roofed structure has been the subject of some modern repairs and consolidation. To the rear is a large, crescent-shaped earthen blast-bank flanked by an outer ditch. Associated with the main compound are the original caretaker's lodge and a tool store situated around 110m to the south east. These have been altered and extended and are in use as a visitor centre and offices, and are therefore not included in the scheduling. The information board and modern fencing on the monument 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.

Legacy

The contents of this record have been generated from a legacy data system.

Legacy System number:

31393

Legacy System:

RSM

Sources

Books and journals
Smith, V, London Archaeologist in The London Mobilisation Centres, Vol. 2, 10, (1975), 244-248

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