The 25th anniversary of the fall of the Berlin Wall has been tempered with warnings of a new Cold War.
German chancellor Angela Merkel has been leading the celebrations in the capital.
She was among thousands of East Berliners who streamed into the West in 1989 when Communist authorities bowed to mounting pressure and eased travel restrictions.
It was to be a pivotal moment in the collapse of communism, and paved the way for the eventual reunification of Gemany.
Speaking at one of the few surviving sections of the wall, Merkel called it an example of the 'human yearning for freedom".
But the Soviet Union’s last leader, Mikhail Gorbachev, remains critical of the West for mishandling the collapse of the Iron Curtain.
Speaking in Berlin on the eve of the anniversary, Gorbachev said: 'European and international politics did not stand the test of renewal of the new conditions of the global world in the post-Cold War era… The world is on the brink of a new Cold War, some are even saying that it has already begun.
"And yet while the situation is so dramatic we do not see the main international body, the UN Security Council playing any role or taking concrete action."
So do barriers ever fall completely between old foes? And are there lessons to be learned elsewhere in the world where separation barriers still exist?
Presenter: Martine Dennis
Karin Lukas - A Journalist who was living in East Germany when the Berlin Wall came down.
Irwin Collier - Director of the John F Kennedy Institute for North American Studies and a specialist on the German reunification.
Steve Sabella - Award-winning Palestinian artist living in Berlin.
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Source: Al Jazeera