Just days after US President Barack Obama walked in his footsteps, Berlin will mark the 50th anniversary of John F. Kennedy's pivotal "Ich bin ein Berliner" speech with celebrations throughout the reunited city.
Kennedy's stirring pledge of solidarity with the besieged western sectors of Berlin still marks the defining touchstone in relations between the United States and Europe's biggest economic power.
The German capital has organised more than 50 events in the run-up to Wednesday's anniversary including tours, lectures, exhibitions and new book publications.
They will culminate in a ceremony at the Schoeneberg town hall where Kennedy spoke to West Berliners who feared any moment could see Soviet tanks roll down their streets.
His eight-hour visit on June 26, 1963 came at a critical stage of the Cold War, and Berlin was on the front line.
It was only a year since the United States and Soviet Union nearly went to war in the Cuban missile crisis, and two years after East Germany's communist regime erected the Berlin Wall, cleaving the city in two.
The United States had done little when Berliners were suddenly cut off from their families and jobs on the other side of the city.
But in an electrifying 10-minute address, Kennedy gave Berliners what they wanted to hear: a condemnation of the Wall and a promise that the free world stood by them.
"Freedom has many difficulties and democracy is not perfect but we have never had to put a wall up to keep our people in, to prevent them from leaving us," the defiant president said, in a firm rejection of communist appeasement.
At the end, Kennedy uttered the immortal words: "All free men, wherever they may live, are citizens of Berlin, and, therefore, as a free man, I take pride in the words 'Ich bin ein Berliner' (I am a Berliner)."
His vow, just five months before he would be assassinated in Dallas, was greeted with rapturous applause from the around 450,000 people thronging the square.
Obama, who spoke Wednesday at the now open Brandenburg Gate, the symbol of German unity, quoted several Kennedy tropes including his most famous German line.
In a toast at a dinner that night hosted by Chancellor Angela Merkel, who grew up in communist East Germany, he acknowledged that JFK had set the bar for any US president abroad almost unattainably high.
"Fifty years ago, as this city prepared to welcome President Kennedy, Berliners were ecstatic," Obama said. "Mayor Willy Brandt tried to calm everybody down -- he told them, don't be too emotional. It didn't work."
Although Kennedy was moved by the reaction, his advisor McGeorge Bundy and Brandt worried that it would only heighten East-West tensions at a time of tentative moves toward detente.
Ulrich Mack, 80, one of the press photographers in Berlin that day, told AFP that people hung from street lamps, road signs and climbed trees just to get a glimpse at the visitor from Washington, and threw reams of confetti.
"It was just a wave of euphoria, it was like being intoxicated -- from the images, from the situation -- it was simply beautiful," said Mack, who just released a book of unpublished photographs from that day.
"It was amazing to see how this sceptical man, who really was quite hostile to Germans, suddenly did an about-face and softened, how he loved shaking hands in the crowd. He was simply overwhelmed by Berlin and the people."
Constanze Stelzenmueller of the German Marshall Fund of the United States said it was easy to forget how high the stakes were when Kennedy walked to the podium.
"Berlin was the biggest pawn of the Soviet-American relationship," she said.
"It's always useful to keep in mind firmly that after 1989 and 1990 there were roomfuls of new street signs found in GDR (communist East German) barracks. In other words, the GDR had always been prepared for a takeover (of West Berlin)."
She said a faint sense of disappointment that Obama did not make a watershed pronouncement in Berlin last week was inevitable.
"Nowadays it's rare that a president gets an opportunity to make a memorable historical pronouncement because things have become less dramatic, less existential," she said.
"Sometimes it's good to remind people that things can be different and that history can repeat itself."