Czech hedgehog

The Czech hedgehog (Czech: rozsocháč or ježek) is a static anti-tank obstacle defense made of metal angle bemes or I-beams (that is, lengths with an L- or H-shaped cross section). The hedgehog is very effective in keeping tanks from getting through a line of defense. It maintains its function even when tipped over by a nearby explosion. Although it may provide some scant cover for infantry, infantry forces are generally much less effective against fortified defensive positions than mechanized units.

The Czech hedgehog's name refers to its origin in Czechoslovakia. The hedgehogs were originally used on the Czech-German border by the Czechoslovak border fortifications - a massive but never-completed fortification system that was turned over to Germany in 1938 after the occupation of the Sudetenland as a consequence of the Munich Agreement.

The Czech hedgehog was widely used during World War II by the Soviet Union in anti-tank defense. They were produced from any sturdy piece of metal and sometimes even wood, including railroad ties. Czech hedgehogs were especially effective in urban combat, where a single hedgehog could block an entire street. Czech hedgehogs thus became a symbol of "defense at all cost" in the Soviet Union; hence the to Moscow defenders, built alongside M-10 in 1966, is composed of three giant Czech hedgehogs.

Czech hedgehogs were part of the defenses of the Atlantic Wall and are visible in many images of the Normandy invasion.

A Czech hedgehog made to specifications could be constructed from any material capable of withstanding at least 60 tonnes-force (600 kN), while being at most 1.4 metres (4 ft 7 in) high. However, such parameters were hard to achieve in makeshift hedgehogs, reducing their usefulness.

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