Berlin ? Massive colorful dominoes painted by German students were placed Saturday 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 7.5-foot-high plastic foam dominoes carried messages, including “We are one people.” The approximately 1,000 dominoes stretching for 1 mile will be toppled Monday 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.

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 Monday as the artistic display comes toppling down.