ATTENTION - EMBARGO, RELEASABLE Thursday

ATTENTION - EMBARGO, RELEASABLE Thursday July 21, 2011 at 2301 GMT - THIS RESTRICTION APPLIES TO ALL MEDIA INCLUDING WEBSITES The wedding dress of Catherine, the Duchess of Cambridge, is pictured at Buckingham Palace, in central London, on July 20, 2011. It was the best kept secret of the royal wedding, but now the Alexander McQueen dress worn by the Duchess of Cambridge when she married Prince William is being put on public display for all to admire. Catherine's ivory and white satin-gazar dress, designed by Sarah Burton, goes on show at Buckingham Palace on Saturday as part of the annual summer opening, where hundreds of thousands of visitors are expected to flock to see it. One million people lined the streets of London to see William and the former Kate Middleton marry on April 29, but few will have got close enough to appreciate the intense effort that went into the stunning gown. AFP PHOTO / LEWIS WHYLD / WPA POOL (Photo credit should read LEWIS WHYLD/AFP via Getty Images)