Britain's most famous landmarks including the London Eye, Houses of Parliament, Downing Street and Gateshead's Millennium Bridge were plunged into darkness for an hour last night to mark the moment Britain first declared war on Germany in 1914.
The lights on some of Britain's most famous landmarks have been switched off for an hour tonight to remember the 17 million who gave their lives in the First World War.
Tower Bridge, the Houses of Parliament and St Paul's Cathedral all went dark from 10 pm.
Britain officially declared war on Germany at 11pm on August 4, 1914. The conflict lasted four years.
As the Lights Out event to remember those who fought and died in WWI happened last night ITV asked our viewers what they did to take part.
Lights on some of Britain's most famous landmarks were extinguished between 10pm and 11pm to remember those who died in WWI.