Germans flew flags at half staff and laid wreaths today to mark the 40th anniversary of the building of the Berlin Wall that divided the city for a generation and became a potent symbol of the Cold War.
In the early hours of August 13, 1961, some 40,000 East German soldiers and police rolled coils of barbed wire along the border to the West to stop a flood of refugees. Berliners awoke to find themselves cut off from family, friends and jobs.
The focus of the commemorations was the some 200 East Germans killed trying to cross what their rulers called the "anti-fascist protection barrier" and the many more who died trying to get across the frontier between East and West Germany.
But this year's anniversary has been hijacked by political bickering ahead of city elections in October.
As Chancellor Gerhard Schroeder laid a wreath of red roses at one of the few segments of Wall still standing, he was booed and jeered by those angry that his Social Democrats (SPD) might form a coalition in the Berlin city hall with the successors to East Germany's communist SED.
"Traitor!" shouted one. "The only good communist is a dead one!" yelled another protester as bodyguards ringed Mr Schroeder.
"The fact that we remember what happened puts us in a situation, no matter what our political affiliation, that we make sure that something like this never happens again," Mr Schroeder said at a nearby documentation center on the Wall.