Thousands of people in Germany have celebrated the 20th anniversary of the fall of the Berlin Wall, an event which hastened the collapse of the Soviet Union, the end of the Cold War and the beginnings of German reunification.

Chancellor Angela Merkel, Germany's first chancellor from the former communist DDR, praised the courage of the thousands of people who stood up against the repressive East German regime. Angela Merkel was among the many thousands of East Germans who crossed the border on the night of 9 November 1989. Chancellor Merkel, accompanied by former Soviet president Mikael Gorbachev and former Polish Solidarity Lech Walesa, took a symbolic walk across the bridge at Bornholmer Strasse, where East Berliners first breached the border on and rushed to freedom.
 

Dozens of events are being held to celebrate the 20th anniversary of the fall of the Wall, many of them around the Brandenburger Tor, which has become a symbol of a reunited east and west Germany. Many world leaders, including US Foreign Secretary Hillary Clinton, Russian President Dmitry Medvedev, French President Nicolas Sarkozy and British Prime Pinister Gordon Brown - representing the World War II allies - have gathered in Berlin to celebrate the historic event.
 

A notable absence is that of Helmut Kohl, who served as chancellor in the years before and after the fall of the Wall and oversaw German reunification. The former chancellor cancelled due to illness. US President Barack Obama sent a surprise video message, saying he "still took inspiration from the courage of East Germans who stood up against their repressive regime."
 

The East German government began erecting its 'anti-fascist protection barrier' in the early hours of 13 August 1961 in a bid to stop the mass exodus of its citizens into West Berlin. At least 136 people were killed attempting to cross 3.6 metre high barrier and escape to the West. Border guards had been ordered to shoot anyone attempting to escape.
 

In a speech, Dr Merkel thanked former Soviet president Mikael Gorbachev for refusing to order a crackdown, "You made all this possible, you courageously let things happen. That was much more than we could have expected". Dr Merkel also thanked former Polish leader Lech Walesa, whose Solidarity trade union was one of the first groups to challenge the might of the Soviet Union.

1000 giant foam rubber dominoes have been set up along a 1.5-kilometre stretch of the wall's route and Mr Walesa tipped the first one over, symbolising the domino effect that led to the collapse of the Soviet Union and the lifting of the Iron Curtain.