LIEGE, BELGIUM - AUGUST 04:  Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge attend a WW1 100 Years Commomoration Ceremony with French President Francois Hollande and King Felipe VI of Spain, at Le Memorial Interallie on August 4, 2014 in Liege, Belgium. Monday 4th August marks the 100th Anniversary of Great Britain declaring war on Germany. In 1914 British Prime Minister Herbert Asquith announced at 11pm that Britain was to enter the war after Germany had violated Belgium's neutrality. The First World War or the Great War lasted until 11 November 1918 and is recognised as one of the deadliest historical conflicts with millions of casualties. A series of events commemorating the 100th Anniversary are taking place throughout the day.  (Photo by Francois Lenoir - WPA Pool /Getty Images)