Borders once guarded with machine guns and barbed wire were thrown open today as the EU expanded its passport-free zone deep into former Communist eastern Europe.

Nine of the countries, which joined the EU in 2004, opened their borders with central Europe at midnight. It is now possible to travel from Latvia in the east all the way to Portugal without showing a visa, passport or ID card.

Angela Merkel, the German Chancellor born on the eastern side of the Iron Curtain, was in Zittau today where the Polish, Czech and German frontiers meet. “This is an historic moment for which we have been waiting for a long time,” she said as the gates were symbolically opened.

The Schengen Treaty zone is a third of the size of the United States and now includes Poland, Slovakia, Hungary, the Czech Republic, Slovenia, Malta, Latvia, Lithuania and Estonia.

Border posts were ceremonially lifted early this morning or after midnight last night and guards left their booths as people walked freely across frontiers that once divided the former Soviet bloc from the West

President Lech Kaczynski of Poland met his Lithuanian counterpart on their shared border. “This is a huge success for all of us. . . Schengen has become a reality,” he said.

In the German town Frankfurt-on-Oder, which borders Poland, about 2,000 people celebrated beneath a firework display as they listened to Beethoven’s “Ode to Joy”, the official EU anthem.

“It is very good. There are no borders, so there is equality. People can communicate now and travel from one place to another without any controls,” said Mikhalina Yszczak, 23, a Polish student, shortly after midnight.

At the Slovak-Austrian crossing, people collected souvenir stamps in their passports as they strolled between the nations in a way impossible to imagine during the Cold War.

“There were soldiers with machine guns here and concrete blocks which even a tank could not run over. Not even a mouse could sneak in,” said Kolomam Prekop, a pensioner.

The Schengen accord was originally signed in 1985 to open the borders between France, Germany, Belgium, the Netherlands and Luxembourg – it now takes in 24 countries.

The UK and Ireland and the only two established EU countries that have refused to open their borders to the rest of Europe.

There are fears that the new borderless zone encompassing 400 million Europeans across 2,500 miles, will make international crime and illegal immigration far simpler.

Yesterday Germany’s police union suggested the opening of borders would allow a crime wave to spread across the continent. Josef Scheuring, head of the GdP union, said it was an invitation to criminals.

Wolfgang Schaeuble, the German Interior Minister, played down the union’s fears. “In an open Europe, thinking only about one's own powers along the borders cannot spell success for the police," he said.

“The abolition of the border controls is of symbolic importance because we are turning the page on the division of Europe."

Illegal immigrants and people smugglers may now find it easier to penetrate the Alpine borders of Slovakia than the tighter security of the German frontier.

One popular route into Europe currently sees illegals from the Middle East or Africa arriving by boat on isolated Croatian islands and making their way onto the mainland and up into Slovenia. From now on, once inside Slovenia the route to across Europe would be unchecked.

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