Pillbox (military)

Pillboxes are concrete dug-in guard posts, normally equipped with loopholes through which to fire weapons. The originally jocular name arose from their perceived similarity to the cylindrical and hexagonal boxes in which medical pills were once sold. They are in effect a trench firing step hardened to protect against small-arms fire and grenades and raised to improve the field of fire.

The concrete nature of pillboxes means that they are a feature of prepared positions. They were probably first used in the Hindenburg Line. This is likely to have been the time when they acquired their incongruous English name. The Oxford English Dictionary's earliest record of the use of the word pillbox in connection with a defensive post is from 13 September 1917, after the German withdrawal onto the Hindenburg Line.

Some pillboxes were designed to be prefabricated and transported to their location for assembly. During World War I, Sir Ernest William Moir produced a design for concrete machine-gun pillboxes constructed from a system of interlocking precast concrete blocks, with a steel roof. Around 1500 Moir pillboxes were eventually produced (with blocks cast at Richborough in Kent) and sent to the Western Front in 1918.

Pillboxes are often camouflaged in order to conceal their location and to maximize the element of surprise. They may be part of a trench system, form an interlocking line of defence with other pillboxes by providing covering fire to each other (defence in depth), or they may be placed to guard strategic structures such as bridges and jetties.

The French Maginot Line built between the world wars consisted of a massive bunker and tunnel complex, but as most of it was below ground little could be seen from the ground level. The exception were the concrete blockhouses, gun turrets, pillboxes and cupolas which were placed above ground to allow the garrison of the Maginot line to engage an attacking enemy.

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