Key facts about the Berlin Wall, which collapsed in 1989 and led to German reunification

Key facts about the Berlin Wall

The Berlin Wall stood for nearly three decades, the most potent symbol of Cold War divisions. Its collapse helped herald the wider collapse of communism across eastern Europe.

The East began construction of the barrier on Aug. 13, 1961 in an attempt to stop the flight of people to the West.

By 1989, the wall stretched nearly 100 miles (155 kilometers) around West Berlin, including 30 miles (43 kilometers) through the city itself. Nearly 12 feet (3.6 meters) high in places, the barrier featured hundreds of watch towers, miles (kilometers) of anti-vehicle trenches, bunkers, barbed wire, signal fences and other obstacles.

— 1945: World War II ends. Berlin — located deep inside the Soviet eastern sector of newly divided Germany — is partitioned into American, British and French sectors in the West, and the Soviet sector in the East.

— 1949: Two new German states are formed: East Germany — officially known as the German Democratic Republic; and West Germany — the Federal Republic of Germany.

— 1952: Concerned at the stream of people flowing to the West — an estimated 2.5 million fled between 1949 and 1961 — East Germany closes the border between East and West Germany, but crossing is still possible at points.

— June 15, 1961: East German leader Walter Ulbricht declares “No one intends to erect a wall.”

— Aug. 13, 1961: East German troops begin sealing off the eastern sector of Berlin with barbed wire and roadblocks to begin building the Berlin Wall.

— Aug. 24, 1961: First person shot dead trying to escape. Guenter Litfin, 24, killed by East German border guards near the downtown Charite hospital. At least 136 people died trying to cross over; thousands more escaped successfully.

— 1962: Work begins on second-generation wall, including a fence about 100 yards (meters) further inside East German territory to create a closely controlled “death strip” between the two barriers.

— June 26, 1963: President John F. Kennedy visits the divided city, proclaiming solidarity with West Berlin with the famous words: “Ich bin ein Berliner.”

— 1965: Construction begins on third-generation wall, using concrete slabs.

— 1975: Work begins on fourth-generation wall, using interlocking concrete segments, and also adding watch towers and other defenses.

— Jan. 19, 1989: East German leader Erich Honecker declares the wall could last another 100 years.

— Summer 1989: Thousands of East Germans flee to West Germany through Hungary.

— Nov. 9, 1989: East Germany opens the Berlin Wall checkpoints.

— Oct. 3, 1990: East and West Germany are reunified.