On ‘Barbed Wire Sunday’, 13 August 1961, the German Democratic Republic closed the border into West Berlin and began the construction of the Berlin Wall. Since the end of World War II, East Germany had lost some 3.5 million citizens from defection to West Germany. The exclave of West Berlin was not protected with a hard border, unlike the national border that had been established in 1952, thus making it the prime route of escape for Germans seeking to leave the ever-more repressive German Democratic Republic. The wall was reinforced using increasingly extreme measures over the years. The last iteration, which began in 1975, featured a 12-ft high (3.6-m) concrete wall, barbed wire, anti-vehicle trenches and hundreds of armed guards who were ordered to shoot defectors. By the time the demolition of the wall started in 1989 after massive protests, 5,000 people had successfully crossed the border while at least 100 were killed during escape attempts.
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