A chronology of the Berlin Wall, erected 28 years ago at the height of Cold War tensions:
Aug. 13, 1961 - East German troops move to seal all access to West Berlin after a mass exodus of hundreds of thousands of East Germans threatens to ruin the economy.In the following days, barbed wire is replaced by concrete barriers. Houses along the border are sealed. Border guards are issued shoot-to-kill orders for all those trying to flee. West Berlin is encircled and isolated from the West.
June 26, 1963 - President Kennedy visits West Berlin. In a show of solidarity with the divided city, he declares to a cheering crowd of 400,000 at the wall: "I am a Berliner."
June 12, 1987 - President Reagan visits West Berlin and calls on Soviet President Mikhail S. Gorbachev to tear the wall down.
March 8, 1989 - The last fatality related to an escape attempt over the Berlin Wall is recorded. An East Berlin man falls to his death after his homemade hot-air balloon deflates prematurely. A total of 80 East Germans have been reported killed trying to flee over the wall since 1961.
Oct. 18, 1989 - Hard-line leader Erich Honecker, who supervised the building of the Wall, is replaced after an unprecendented wave of unrest and the exodus of thousands of citizens.
Nov. 3, 1989 - In the first direct challenge to the wall's purpose, East Berlin announces that East Germans who want to flee West can do so over the Czechoslovak border. Tens of thousands do so.
Nov. 9, 1989 - The Communist leadership declares that citizens can travel directly to West Germany through East German checkpoints with proper documentation. Thousands of East Berliners make their way to the Berlin Wall. Officials waive the requirement for visas and thousands stream over to West Berlin for a night of celebration.
Nov. 10, 1989 - The celebrations continue as East Germans open more crossing points through the wall.
Nov. 11, 1989 - More than 1 million people cross the wall to the West.