In 2006 a visitor to the Fitzwilliam Museum in Cambridge caused more than £500,000 worth of damage when he slipped down a stairway and smashed a set of 300-year-old Qing vases that had stood happily on a shelf for 40 years. Spokespeople for the museum said he was believed to have tripped on an untied shoelace but was unharmed by the accident.