Ceremonies marking the 20th anniversary of the fall of the Berlin wall are moving towards their climax as world leaders, past and present, join tens of thousands of tourists and well wishers on the streets of the city about now. German Chancellor Angela Merkel will join the former Soviet President Mikhail Gorbachov and the former Polish President Lech Walesa in a symbolic walk across the first former check point to be opened. Earlier today, beside a piece of wall which has been left standing there was music and there were speeches recalling the dramatic events of November 9th of 1989, the day when the barrier finally cracked. Among the group were school children, in groups they placed red roses in tiny gaps in the concrete barrier to honour the memory of more than 130 people who were killed trying to escape to West Berlin.