Germany, amid big crowds and some special appearances by world leaders, is celebrating the 20th anniversary of the Berlin Wall’s fall. And the wall falls again – this time a symbolic wall of giant dominoes, many of them created by children who live in countries where there are, in effect, political walls. The BBC has the details in this report:

UPDATE: Secretary of State Hillary Clinton represented the United States at the celebration but President Barack Obama made a surprise visit…via video address.