Their Royal Highnesses Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge kiss on the balcony at Buckingham Palace on April 29, 2011 in London, England. The marriage of the second in line to the British throne was led by the Archbishop of Canterbury and was attended by 1900 guests, including foreign Royal family members and heads of state. Thousands of well-wishers from around the world have also flocked to London to witness the spectacle and pageantry of the Royal Wedding. (Photo by Peter Macdiarmid/Getty Images)

An installation consisting of a series of bird boxes is displayed in a tree in Duncan Terrace Gardens in Islington on March 24, 2011 in London, England. The boxes by artists Bruce Gilchrist and Jo Joelson of “London Fieldworks”, were designed to reflect the architecture of the Georgian terraces and flats that surround the park in the community gardens. (Photo by Dan Kitwood/Getty Images)

A Sotheby's employee holds a 110.03 carat sun-drop diamond on October 24, 2011 in London, England. The diamond is the largest yellow pear-shaped diamond in the world, and is expected to fetch between $11-15 Million USD when it is sold at auction at Sotheby's Auction house in London. (Photo by Dan Kitwood/Getty Images)

A gallery assistant holds a print of an Andy Warhol artwork estimated to fetch 1,500 GBP in Bonhams auction house on November 25, 2011 in London, England. The auction of prints of works ranging from old masters to contemporary artists takes place in London on November 29, 2011. (Photo by Oli Scarff/Getty Images)

The under-construction Shard building on December 5, 2011 in London, England. The 80 storey skyscraper will be Europe's tallest mixed-use building when it is completed in May 2012; it will contain offices, restaurants, residential apartments as well as a five star hotel. (Photo by Dan Kitwood/Getty Images)

Lisa Snowdon (C) takes part in the launch of the new Veet Easywax campaign in a bid to find “Britain's Greatest Legs” on February 23, 2012 in London, England. (Photo by Tim Whitby/Getty Images)

Models turned into “humanoid” robots pose on a train at Waterloo Station on October 2, 2016 in London, England for the launch of new Sky Atlantic TV drama Westworld. (Photo by Matt Alexander/PA Wire)

People dressed as zombies participate in a parade for World Zombie Day 2016 in London's West End, Britain on October 9, 2016. (Photo by Splash News and Pictures)