 The ceremony began after a filmed countdown showing numbers from around London on such locations as road signs , 10 Downing Street and the Palace of Westminster clock tower , with a camera panning up the River Thames over Tower Bridge before turning left towards the stadium . The audience then completed a 10 @-@ second countdown to the start of the ceremony , to the chimes of Big Ben . The arena had been transformed into a huge representation of the Union Flag in black and white , with ramps and famous London landmarks such as the London Eye , Big Ben , Battersea Power Station and the Gherkin . Newspaper cutouts on both the set and road vehicles sought to show a " day in the life of London " , with words from British literary figures such as William Shakespeare , J. R. R. Tolkien and Poet Laureate Carol Ann Duffy . 
