Celebrations have begun across Europe to mark the enlargement of the European Union to a 25-nation economic and political bloc of 450 million people.
Lech Walesa
EU enlargement takes effect at 10 p.m. tonight (midnight CET) and 10 new nations will then officially become members.
Eight former Warsaw Pact members Czech Republic, Estonia, Hungary, Latvia, Lithuania, Poland, Slovakia and Slovenia will join Cyprus and Malta to raise the EU's membership from 15 to 25 and turn the bloc into the world's largest free trade area.
Star-studded blue EU flags will go up and fireworks light the sky at midnight across eastern and central Europe, marking the largest single enlargement of the European Union since its inception.
An estimated 50,000 people were expected in Sandymount this evening for a spectacular fireworks display to mark the accession.
"Poland's entrance into the European Union fulfills my dreams and lifetime work," said Mr Lech Walesa, whose Solidarity movement toppled communism in Poland in 1989, said today.
The EU faces profound change as it tries to integrate poorer east Europeans and stay manageable with its border posts moving 1,000 kilometres east, to the frontiers of Belarus, Russia and Ukraine.
"May 1 will be a milestone in the history of Europe," EU Enlargement Commissioner Mr Guenter Verheugen said in Warsaw. "It is Europe's response to the end of the Cold War and an opportunity to heal the wounds of the past, wounds of war and dictatorship."
Scheduled alongside the official pomp are some unorthodox celebrations.
Lithuanians will switch on lights countrywide to make the land glow on satellite pictures; Hungarians will dump unwanted belongings in a pile at a central Budapest square.
In Estonia, 20,000 volunteers will start planting a million trees; Czechs and their German neighbours will create rainbows bridging "West" and "East" using water cannon and floodlights.
Earlier tonight, several hundred protestors participated in a Critical Mass slow cycle through the streets of Dublin. Several protests and carnival events are planned for tomorrow to mark May Day and the accession of the new EU states.
Celebrations across the continent on Saturday, culminate in the enlarged EU's first summit, to be held in Dublin.