Czechoslovakian border fortifications during the Cold War

The protection of borders between the Czechoslovak Socialist Republic (CSSR) and so called Capitalist countries of Western Europe, namely with West Germany and Austria, in the Cold War era and especially after 1951, was provided by special troops of the Pohraniční Stráž (English: the Border Guard) and system of engineer equipment which created the real "Iron Curtain". The purpose was to prevent citizens of the Eastern Bloc escaping to the West, although official reports stated it was to keep the enemy's spies and saboteurs out of Czechoslovakia. The border system of Czechoslovakia was not as elaborate and fortified as that of the Inner German border or the Berlin Wall, but it was considered difficult to cross the border undetected.

After World War II and liberation of country the original borders of Czechoslovakia were restored and special units of police (SNB) were to protect the borders together with the army. Following the communist takover in the government, thousands of opponents of the communist regime tried to escape the country. For individuals or small groups it was quite easy to avoid the guards and cross the borders, though it was dangerous if they were spotted, as the guards were allowed to shoot the intruders on sight. About 10,000 people including 50 prominent politicians crossed the borders in the first year after the political change.

Consequently, the independent HQ of Border Guard was created but the number of crew was nearly the same (about 6000 men) as the detection of potential emigrants by regular police was preferred. The so-called "forbidden zone" was established up to 2 km from the border in which no civilians could reside. A wider region, so called "border zone" also existed, up to 12 km from the border, in which no "disloyal" or "suspect" civilians could reside or work. For example, the entire Aš-Bulge creating the most problematic part of the border territory fell within the border zone.

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