
The London Eye, 10 Downing Street and the Houses of Parliament were among Britain's landmarks which turned out their lights for an hour at 10pm last night to remember those who died in the First World War.

Homes, businesses and public buildings across the UK were asked to leave on a single light or candle to commemorate the moment then-prime minister Herbert Asquith declared Britain had entered the First World War at 11pm on August 4, 1914.

Buildings around the country yesterday took part in the 'hour of reflection' between 10pm and 11pm, leaving just a light illuminating a window.

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Darkness: Buildings around the country, including Tower Bridge and 10 Downing Street, took part in the 'hour of reflection' between 10pm and 11pm yesterday

In the dark: The Houses of Parliament in London after the lights were turned off as part off the national 'Lights Out' campaign of remembrance

The clock face of Big Ben was the only light illuminating Westminster at 11pm last night, which marked the moment the First World War began 100 years ago Before: A photo of the Houses of Parliament before the lights were turned out to mark 100 years since Britain entered the First World War London Eye: People across the UK were invited to turn their lights out from 10pm to 11pm leaving on a single light or candle Before the blackout: The London Eye, on the South Bank in central London, with lights on ahead of the Lights Out event across Britain

A single light illuminated Tower Bridge in London last night as traffic and pedestrians pass over the crossing as the centenary of World War One is marked

The bridge lifts up to allow a boat to pass through prior to the beginning of the Lights Out event where many central London landmarks took part Landmark building: The Shard in central London is seen with the spire lights switched off (left), and just before (right) Light in the distance: The Cenotaph in central London during an hour's darkness to mark 100 years since the beginning of First World War

As the lights went out, people gathered at the Cenotaph in Whitehall to light their own candles and lay their own flowers and wreaths

The Menin Gate in Ypres, Belgium sits in near darkness, with only one symbolic single light illuminating the Memorial

The Menin Gate, which is maintained by the Commonwealth War Graves Commission, pictured before the lights were turned out

Current troops serving in Afghanistan stand in the darkness of Camp Bastion, which was only lit by a single light. Personnel from all three armed forces took part in the vigil and they were joined by members of the US Marine Corps

The plan was inspired by the words of then-foreign secretary Sir Edward Grey, who said just before the announcement: 'The lamps are going out all over Europe; we shall not see them lit again in our lifetime.'

Other buildings taking part in an hour-long lights switch-off last night were Broadcasting House in London, the Eden Project in Cornwall, St Paul's and Durham cathedrals, and Wales Millennium Centre in Cardiff.

Also expected to join in were office buildings including Barclays in Canary Wharf and Marks & Spencer.

Prime Minister David Cameron has backed the idea and is urging as many people as possible to take part.

Bowing her head: The Duchess of Cambridge during a ceremony at the St Symphorien Cemetery in Belgium



Prince Harry, Belgium's Queen Mathilde, the Duchess of Cambridge Belgium's King Philippe, Prime Minister David Cameron and Prince William in Mons, Belgium

Commemoration: The Duke of Cambridge (centre) and David Cameron (second right) at the ceremony at St Symphorien Cemetery in Mons, Belgium Camilla, Duchess of Cornwall, , accompanied by Dean of Westminster the Reverend John Hall, right, walks by the tomb of unknown warriors as she attends a candlelit vigil and prayer service to commemorate the centenary of the outbreak of the First World War at Westminster Abbey The duchess of Cornwall, second left, extinguishes the remaining flame at the Grave of the Unknown Warrior Camilla sits in reflection as she attends the ceremony. In one of her most significant public engagements to date, the Duchess of Cornwall attended the vigil at Westminster Abbey

A single light was shining from Buckingham Palace like many other buildings across the country as 100 years since Britain entered World War One was remembered

Unusual sight: A single window is illuminated in Buckingham Palace as the lights are turned off on iconic buildings around London



Poppies: Piccadilly Circus in London displays memorial images as the lights are turned off on buildings and the UK marks the centenary of the outbreak of the war

Black scene: Piccadilly Circus and the Criterion Theatre turn off their lights to mark the centenary of the outbreak of the First World War

The lights of Picadilly Circus light up central London as people gathered at the landmark to commemorate 100 years since the outbreak of the First World War

A man pauses to reflect at the remembrance event in Piccadilly Circus, where the screens showed memorial images to those gathered

The Houses of Parliament are seen from Westminster Bridge as the lights are turned off on iconic buildings around London to mark the centenary of the outbreak of the war

'Spectra' by Japanese artist Ryoji Ikeda: Acting as beacon for the capital, a monumental pillar of light beamed into the clouds from Victoria Tower Gardens Shining up: Lights go out across London as the city marks the centenary of the outbreak of the World War One

A man gazes up at the Spectra light installation, left, while a woman takes a picture of the light, which was the only beam to light up London, which fell into darkness at 10pm

Trafalgar Square in central London (left), and candles illuminate the names of missing soldiers at the Menin Gate Memorial to the Missing in Ypres, Belgium (right)

Seafront: Blackpool Tower in Lancashire displays a single light on the day the nation commemorates 100 years since Britain joined the First World War

Lights on: Blackpool Tower stands illuminated with a heart Union Jack to mark the 100-year anniversary of Britain joining the First World War

Passengers at Bristol Temple Meads railway station switched off their lights as part of the campaign by the Royal British Legion Temple Meads station lit up pre 10pm ahead of the beginning of the Lights Out initiative to mark the exact moment war began 100 years ago

The Library of Birmingham displayed a simple row of white lights on each floor to remember those who fought and lost their lives in the First World War

A single candle was projected on to the front of the Grade I listed Royal Liver Building in Liverpool last night as part of the Lights Out initiative A Vigil of Prayer and Penitence was held at Bath Abbey last night, where each member of the congregation lit their own candle The idea of Lights Out was promoted by the Royal British Legion, who say they have a number of initiatives planned to mark the conflict's centenary

The lights across Glasgow University were dimmed as the city fell into darkness and paused to remember the 100th anniversary of the beginning of the First World War

A simple single lantern lights the dome above the Great Hall of the Castle Howard estate near York last night He said: 'Lights Out is a way for everyone to mark the First World War centenary and I would encourage people to take part and turn off their lights tomorrow at 10pm for an hour, apart from a single light or candle. 'This will be a personal gesture in remembrance of all those who made the ultimate sacrifice for us 100 years ago. They must never be forgotten.' The idea is being promoted by the Royal British Legion, who brought together celebrities including Jeremy Paxman, Twiggy, David Gandy and Louis Smith for a video to encourage people to take part.

Westminster Abbey: Camilla, Duchess of Cornwall, centre, with the Dean of Westminster the Reverend John Hall, right, walks by the tomb of the Unknown Warrior An oil lamp burns next to the tomb of the Unknown Warrior in Westminster Abbey, which is decorated with flowers Candelit evening: Members of the congregation look on during the vigil at Westminster Abbey in central London Helping hand: Chelsea pensioners light their candles during a candlelit vigil and prayer service to commemorate the First World War starting at Westminster Abbey

Preparations at the Tomb of the Unknown Warrior in London's Westminster Abbey ahead of the ceremony last night

A vigil service was held at the Abbey during where members of the congregation extinguished candles to mark 100 years since the start of the First World War

The Houses of Parliament, pictured taking part in a similar scheme in 2007, switched their lights off at 10pm last night as part of an initiative to commemorate Britain entering the First World War Prime Minister: David Cameron (left) has been encouraging people to take part in the initiative, which is inspired by the words of former Foreign Secretary Sir Edward Grey (right), who said on the eve of war: 'The lamps are going out all over Europe; we shall not see them lit again in our lifetime'

Charles Byrne, Director of Fundraising at The Royal British Legion, said: 'Sir Edward Grey's stirring words are the campaign's foundation.

'Our vision is that over one million candles will be lit across the UK, commemorating every Service man and woman who died during WW1.

'We hope to see candles lit at every war memorial, community centre and home in every village and in every community.

'This is one of a number of initiatives the Legion has undertaken to commemorate the anniversary of the First World War, when we hope to pass the torch of remembrance onto a younger generation ensuring there will always be a living legacy to those who sacrificed their today for our tomorrows.'

Coinciding with the start of the initiative at 10pm, a vigil service will be held at Westminster Abbey during which members of the congregation will extinguish candles until there is just one left alight on the tomb of the unknown soldier, which will be snuffed out by the Duchess of Cornwall at 11pm.

People in Seaham, County Durham placed candles and poppies at the town's War Memorial as they held a vigil to remember the fallen