Tank trap

Dragon's teeth (German: Drachenzähne) are square-pyramidal fortifications of reinforced concrete first used during the Second World War to impede the movement of tanks and mechanised infantry. The idea was to slow down and channel tanks into killing zones where they could easily be disposed of by anti-tank weapons.

They were employed extensively, particularly on the Siegfried Line.

In practice, the use of combat engineers and specialist clearance vehicles enabled them to be disposed of relatively quickly, and they proved far less of an obstacle than many had expected. The obstacles could also simply be buried using bulldozers and dump trucks.

Dragon's teeth were used by several armies in the European Theatre. The Germans made extensive use of them in the Siegfried Line and the Atlantic Wall. Typically, each "tooth" was 90 to 120 cm (3 to 4 ft) tall depending on the precise model.

Land mines were often laid between the individual "teeth", and further obstacles constructed along the lines of "teeth" (such as barbed wire to impede infantry, or diagonally-placed steel beams to further hinder tanks). The French army employed them in the Maginot Line, while many were laid in the United Kingdom in 1940–1941 as part of the effort to strengthen the country's defences against a possible German invasion.

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