1. The fall of the Berlin Wall happened by mistake.

At a press conference on the evening of November 9, 1989, East German politburo member Günter Schabowski prematurely announced that restrictions on travel visas would be lifted. When asked when the new policy would begin, he said, “Immediately, without delay.” In actuality, the policy was to be announced the following day and would still have required East Germans to go through a lengthy visa application process. Schabowski’s confused answers and erroneous media reports that border crossings had opened spurred thousands of East Berliners to the Berlin Wall

At the Bornholmer Street checkpoint, Harald Jäger, the chief officer on duty, faced a mob growing in size and frustration. Receiving insults, rather than instructions, from his superiors and nervously expecting results of his cancer diagnostic tests the next day, the overwhelmed Jäger opened the border crossing on his own, and the other gates soon followed.

2. The Berlin Wall was erected more than 15 years into the Cold War.

More than 2 million East Germans, most of them skilled laborers and professionals, fled to the West between 1949 and 1961. The Soviet Union had rejected East Germany’s original request to build the wall in 1953, but with defections through West Berlin reaching 1,000 people a day by the summer of 1961, Soviet leader Nikita Khrushchev finally relented. The residents of Berlin awoke on the morning of August 13, 1961, to find barbed wire fencing had been installed on the border between the city’s east and west sections. Days later, East Germany began to fortify the barrier with concrete.

3. The Berlin Wall was actually two walls.

The 27-mile portion of the barrier separating Berlin into east and west consisted of two concrete walls between which was a “death strip” up to 160 yards wide that contained hundreds of watchtowers, miles of anti-vehicle trenches, guard dog runs, floodlights and trip-wire machine guns.

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4. More than 100 people died trying to cross the Berlin Wall.

The Centre for Research on Contemporary History Potsdam and the Berlin Wall Memorial Site and Documentation Center report that at least 138 people were shot dead, suffered fatal accidents or committed suicide after failed escape attempts across the Berlin Wall. Other researchers place the death toll even higher. The first victim was Ida Siekmann, who died on August 22, 1961, after attempting to leap to a West Berlin street below her fourth-floor East Berlin apartment window. The last fatality occurred in March 1989 when a young East German attempting to fly over the wall in a hot air balloon crashed into power lines.

5. More than 5,000 escaped by going over and under the Berlin Wall.

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A statue of East German soldier Conrad Schumann, who famously jumped across barbed wire into West Berlin in 1961.

The first defector to escape across the Berlin Wall was 19-year-old East German border guard Corporal Conrad Schumann, who was immortalized on film as he leapt over a 3-foot-high roll of barbed wire just two days after East Germany sealed the border. As the Berlin Wall grew more elaborate, so did escape plans. Fugitives hid in secret compartments of cars driven by visiting West Berliners, dug secret tunnels and crawled through sewers. The three Bethke brothers pulled off the most spectacular escapes. Eldest brother Ingo escaped by floating on an inflatable mattress across the Elbe River in 1975, and eight years later brother Holger soared over the wall on a steel cable he fired with a bow and arrow to a rooftop in West Berlin. In 1989 the pair flew an ultra-light plane over the wall and back to pick up youngest brother Egbert.

6. John F. Kennedy expressed relief when the Berlin Wall was erected.

In June 1961, Khrushchev warned President John F. Kennedy that he would blockade West Berlin if Western forces were not removed, a belligerent act that could lead to war. When Kennedy heard news that the communists had walled off East Berlin instead of cutting off West Berlin, he confided to an aide, “It’s not a very nice solution, but a wall is a hell of a lot better than a war. This is the end of the Berlin crisis. The other side panicked—not we. We’re going to do nothing now because there is no alternative except war.”

7. Kennedy did not tell Berliners he was a 'jelly doughnut.'

On June 26, 1963, Kennedy famously told a crowd at the Berlin Wall, “Ich bin ein Berliner.” The president intended to express solidarity with the citizens of Berlin by saying he was one of them, but some critics claimed that by adding the indefinite article “ein,” he actually called himself a jelly doughnut, known in much of Germany as a “Berliner.”

Linguists say, however, that the president did not commit a grammatical faux pas because “ein” is required when the speaker is speaking figuratively, not literally, about being of a certain nationality, as was obviously the case with Kennedy. In addition, the jam-filled pastry known as a “Berliner” in the rest of Germany is called a “pfannkuchen” in Berlin, so there would have been no confusion among the listeners.

8. East Germany called the wall the 'Antifascist Bulwark.'

Rather than keeping its citizens in, the East German government claimed it erected the Berlin Wall to keep Western fascists, spies and ideas out. Two weeks after ordering the construction of the “Antifaschistischer Schutzwall,” East German leader Walter Ulbricht claimed, “We have sealed the cracks in the fabric of our house and closed the holes through which the worst enemies of the German people could creep.”

9. The Brandenburg Gate had once been part of an 18th-century wall.

Prussian King Frederick William II commissioned the iconic triumphal arch straddling East and West Berlin that served as the iconic backdrop for famous presidential speeches by Kennedy and Ronald Reagan. When completed in 1791, the Brandenburg Gate was incorporated into the city’s original Customs Wall, which ringed the city beginning in the 1730s.

10. A piece of the wall stands in the bathroom of a Las Vegas casino.

Official demolition of the Berlin Wall began in the summer of 1990. More than 40,000 wall sections were recycled into building materials used for German reconstruction projects, but a few hundred segments were auctioned off and are now scattered around the globe from the Vatican gardens to the men’s room of the Main Street Station Casino in Las Vegas, where urinals are mounted on a graffiti-covered wall segment protected behind glass.