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It was a day for waving flags...

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... and removing barriers between nations, sometimes literally.

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In Cyprus, children played a major role in the street celebrations.

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The Hungarian government hosted breakfast on a Budapest bridge for children born on 1 May - the first day of Hungary's EU membership.

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And Budapest's first "EU-baby" was given 2004 euros by the city mayor.

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Irish PM Bertie Ahern, President of the European Council, was much in demand.

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But not everyone in the new EU member states was celebrating.