LONDON (Reuters) - A natural phenomenon rather than a design fault caused London's Millennium Bridge to wobble and sway, forcing its closure just two days after opening in 2000.

The elegant pedestrian walkway was conceived as a blade of light linking the south bank of the River Thames to the City of London. But as large crowds walked across the steel structure on opening day in June 2000, the 320-meter long bridge swayed from side to side because of a phenomenon known as collective synchronisation.

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Didn't Mythbusters disprove this last season?