London Defence Positions

The London Defence Positions were a late 19th century scheme of earthwork fortifications in the south-east of England, designed to protect London from foreign invasion landing on the south coast. The positions were a carefully surveyed contingency plan for a line of entrenchments, which could be quickly excavated in a time of emergency. The line to be followed by these entrenchments was supported by thirteen permanent small polygonal forts or redoubts called London Mobilisation Centres, which were equipped with all the stores and ammunition that would be needed by the troops tasked with digging and manning the positions.

The 1859 Royal Commission on the Defence of the United Kingdom report on Britain's defences believed that London was practically undefendable; they proposed a fort at Shooters Hill to defend the Royal Arsenal at Woolwich, but it was never acted upon. Following a number of proposals by senior military figures, an 1888 memorandum written by Colonel John Charles Ardagh envisaged a scheme of simple earthworks for infantry and moveable armaments, intended to be dug and manned in an emergency by the Volunteer Force, the line being supported by permanent works, the London Mobilisation Centres, at 5 mile (8 km) intervals, which acted as stores and magazines. The London Defence Scheme was announced in Parliament in March 1889 by the Secretary of State for War, Edward Stanhope, by which time the 13 sites for the Mobilisation Centres had already been purchased at a cost of £25,000.

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