It was heralded as the ultimate library, museum and art gallery all rolled into one and just a click of a mouse away. But Europeana, the online repository of millions of the finest artefacts from Europe’s top cultural institutions, crashed within hours after an unexpected demand from users to view the Mona Lisa.

Europeana was geared up to cope with 5 million hits – mouse-clicks – per hour. Its organisers pulled the site down after just a day when hits peaked at 20 million and its three computer servers could not cope with simultaneous interest in Leonardo da Vinci’s iconic portrait from around 3,000 users at exactly the same moment.

The site, seen as a rival to Google’s growing online book repository Book Search, will return in mid-December after boosting its capacity with another three servers. It will offer two million books, maps, musical scores and recordings, videos and works of art from the Louvre in Paris to the Rijksmuseum in Amsterdam and the British Library.

EU officials today portrayed the misfired launch as a sign of the project’s success.

“Europe’s new digital library was overwhelmed by the interest taken by millions of users,” said a spokesman for the EU’s information commissioner, Viviane Reding.

“We had thousands of users searching in the very same second for the Mona Lisa and this is something that the server had problems with.

“It is not a failure, it is an unexpected success. We all see it as confirmation that this project is worth doing and aim to have 10 million objects on the site by 2010.”

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