Technicians carry out cleaning and maintenance work on one of the faces of the Great Clock atop the landmark Elizabeth Tower that houses Big Ben, attached to the Houses of Parliament, in London, on August 19, 2014. A team of abseilers is busy this week cleaning up the clock faces at the Houses of Parliament in London. The specialist technicians descend the most famous London landmark by rope to clean and inspect the four clock faces. The clock on the Elizabeth Tower was last cleaned in 2010 and besides cleaning up any dirt that has accumulated since then, the experts will conduct a photographic survey to check the dials for damage. AFP PHOTO / BEN STANSALL