BERLIN -- Massive colorful dominoes painted by German students were placed yesterday along the former path of the Berlin Wall to mark the 20th anniversary of the opening of the barrier that divided the city for nearly three decades.

Many of the upright 71/2-foot-high plastic foam dominoes carried messages, including "We are one people." The approximately 1,000 dominoes stretching for one mile will be toppled tomorrow as part of wider celebrations of the wall's fall.

One labeled "bleeding heart" showed a sword cutting through the city of Berlin, starting a crimson flow of blood speckled with crosses.

"Everyone has walls in their heads to a certain extent," said Berlin resident Stefan Schueler as he perused the domino display. "It's always a good thing if one can break them down, and I think this is a good symbol."

Former Polish leader Lech Walesa, whose pro-democracy movement Solidarity played a key role in ending communism in Eastern Europe, is to tip the first domino tomorrow as the artistic display comes toppling down.

U.S. Secretary of State Hillary Rodham Clinton, British Prime Minister Gordon Brown, French President Nicolas Sarkozy and Russian President Dimitry Medvedev also are expected to be on hand tomorrow for the formal commemorations of the wall's opening on Nov. 9, 1989.

German Chancellor Angela Merkel, herself a resident of East Germany when the wall fell, said in her weekly podcast yesterday that it was a day that "changed the lives of many people including me."

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