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Oscar Aquilina sent in this picture of the EU enlargement celebrations over the Grand Harbour, Malta.

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Glenn Riley: As a Brussels ex-pat, I saw the European flag flying at Cinquantenaire Park.

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Andrius Dagilis: Kulautuvos High School celebrated Lithuania's accession to the European Union.

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Andrius Sarcevicius: This girl, in front of Vilnius Cathedral in Lithuania, was wearing a dress made from the European flag.

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Franz Danner and Christian Huber (on the Polish-German border): We all look forward to having a great relationship with our new neighbours.

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Robin Taylor: Two Oxford University societies joined forces and sang a rousing rendition of the EU anthem.

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Chris and Paul, from Cambridge: We marked the momentous event by sampling the food, drink and music of our old and new European friends.