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The yellow stars of the EU flag are being raised alongside national colours across the 10 states joining the EU.

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Austrian, Italian and Slovenian leaders exchanged smiles and handshakes at their border to celebrate becoming EU brothers.

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Bad weather in Brussels prevented 25 EU hot air balloons taking off, but this did not dampen the party atmosphere.

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In Lithuania - which used to be part of the Soviet Union - the day in history was marked with a giant mural.

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In Germany, a village is celebrating being named as the geographical centre of the new EU.

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A special steam train carried Czech passengers across the German border into Bavaria to celebrate enlargement there.

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This Hungarian truck will be the first commercial vehicle to cross the border without a custom inspection.

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For some EU officials, enlargement means the culmination of years of work...

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...and for many citizens, it means looking West after generations of looking to Moscow...

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...but the younger generations will not remember a time outside the EU.