Royal family commemorates the start of World War I
Catherine, The Duchess of Cambridge, Prince William, Duke of Cambridge and Prince Harry visit The Tower of London's 'Blood Swept Lands and Seas of Red' ceramic poppy installation by artist Paul Cummins, commemorating the 100th anniversary of the outbreak of First World War, August 5, 2014.
London, England
Light is beamed into the sky from Trafalgar Square to mark the 100th anniversary of the outbreak of World War One, in London, Aug. 4, 2014.
Mons, Belgium
From left: Britain's Prince Harry, Mons city mayor Nicolas Martin, Britain's Catherine, Duchess of Cambridge and Prince William appear on a balcony at the Mons town hall with Belgium's outgoing Prime Minister Elio Di Rupo, Aug. 4, 2014. Dignitaries attended ceremonies to commemorate the 100th anniversary of the outbreak of World War I.
Mons, Belgium
Catherine, Duchess of Cambridge, left, King Philippe of Belgium, British Prime Minister David Cameron and Prince William, Duke of Cambridge pay their respects at St Symphorien Military Cemetery in Mons, Belgium, Aug. 4, 2014.
London, England
A guard places a lantern at the front door of Number 10 Downing Street during "Lights Out", as part of commemorations to mark the 100th anniversary of the outbreak of World War I (WWI), in London, England, Aug. 4, 2014.
Aberdeenshire, England
Queen Elizabeth attends a commemoration service at Crathie Kirk Church in Crathie, Aberdeenshire Aug. 4, 2014. Dignitaries took part in events to commemorate the 100th anniversary of the outbreak of World War I.
Liege, Belgium
Prince William, Duke of Cambridge, and Kate, Duchess of Cambridge, attend a World War I 100 Years Commemoration Ceremony with French President Francois Hollande and German President Joachim Gauck at Le Memorial Interallie in Liege, Belgium, Aug. 4, 2014.
Aug. 4 marks the 100th Anniversary of Great Britain declaring war on Germany. In 1914 British Prime Minister Herbert Asquith announced at 11 p.m. that Britain was to enter the war after Germany had violated Belgium's neutrality. The First World War or the Great War lasted until November 1918 and is recognized 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.
Liege, Belgium
Prince William is watched by Kate, Duchess of Cambridge, left, and Queen Mathilde of Belgium as he walks to give a speech during a World War I 100 Years Commemoration Ceremony at Le Memorial Interallie in Liege, Belgium, Aug. 4, 2014.
Liege, Belgium
Kate, Duchess of Cambridge, talks with French President Francois Hollande as they attend commemorations marking 100 years since the invasion of Belgium by Germany at the start of World War I in Liege, Belgium, Aug. 4, 2014.
Liege, Belgium
Prince William and Kate, Duchess of Cambridge, attend a World War I 100 Years Commomoration Ceremony at Le Memorial Interallie in Liege, Belgium, Aug. 4, 2014.
Liege, Belgium
Kate, Duchess of Cambridge, attends a World War I 100 Years Commemoration Ceremony at Le Memorial Interallie on Aug. 4, 2014, in Liege, Belgium.
Liege, Belgium
Queen Mathilde of Belgium attends a WW1 100 Years Commomoration Ceremony at Le Memorial Interallie in Liege, Belgium, Aug. 4, 2014. Aug. 4 marks the 100th Anniversary of Great Britain declaring war on Germany.
Liege, Belgium
Veterans attend a ceremony at the Cointe Inter-allied Memorial, commemorating the 100th anniversary of the outbreak of World War I in Liege, Belgium, Aug. 4, 2014.
Ypres, Belgium
A shaft of sunlight falls on the names of the missing at the Menin Gate Memorial on the centenary of the Great War in Ypres, Belgium. Today marks the 100th anniversary of Great Britain declaring war on Germany.
Glasgow, Scotland
Prince Charles attends a wreath-laying ceremony at the cenotaph in Glasgow to commemorate the centenary of the start of World War I in Glasgow, Scotland, Aug. 4, 2014.
Glasgow, Scotland
Prince Charles, Prince Of Wales, attends a wreath-laying ceremony at the cenotaph in Glasgow to commemorate the centenary of the start of World War I in Glasgow, Scotland, Aug. 4, 2014.
Glasgow, Scotland
Deputy Prime Minister Nick Clegg and Labour leader Ed Miliband attend a wreath-laying ceremony at the cenotaph in Glasgow to commemorate the centenary of the start of World War I in Glasgow, Scotland, Aug. 4, 2014.
The First World War or the Great War lasted until November 1918 and is recognized as one of the deadliest conflicts in history with millions of causalities. A series of events commemorating the 100th anniversary are taking place throughout the day.
Glasgow, Scotland
Prince Charles, Prince Of Wales salutes with Prime Minister David Cameron at a wreath-laying ceremony at the cenotaph in Glasgow, Scotland, to commemorate the centenary of the start of World War I, Aug. 4, 2014.
Glasgow, Scotland
Prime Minister David Cameron looks on as Prince Charles signs a book during a memorial service at Glasgow Cathedral to mark the centenary of the outbreak of World War I in Glasgow, Scotland, Aug. 4, 2014.
Folkestone, England
Prince Harry attends the "Step Short" commemorative event in Folkestone, England, to mark the centenary of the First World War, Aug. 4, 2014.
Folkestone, England
Balloons are released with the names of the soliders who lost their lives as part of the commemorative event in Folkestone, England, to mark the centenary of the First World War, Aug. 4, 2014.
Folkestone, England
Prince Harry attends the "Step Short" commemorative event in Folkestone to mark the centenary of the First World War in Folkestone, England, Aug. 4, 2014.
Folkestone, England
Prince Harry attends the "Step Short" commemorative event in Folkestone to mark the centenary of the First World War in Folkestone, England, Aug. 4, 2014.
Folkestone, England
Prince Harry attends the "Step Short" commemorative event in Folkestone, England, to mark the centenary of the First World War, Aug. 4, 2014.
Bovington, England
Replica World War One German and British fighter aircraft take part in a re-enactment of a dog fight at the Tank Museum in Bovington England, Aug. 4, 2014. Aug. 4, 2014 marks the 100th anniversary of Great Britain's declaration of war on Germany.
Bovington, England
Members of the Great War Society living history group dressed as 4th Battalion the Middlesex Regiment stand under a shower of a million poppy flowers representing the dead during a World War I centenary ceremony at the Tank Museum in Bovington, England, Aug. 4, 2014.
Bovington, England
Members of the Great War Society living history group dressed as 4th Battalion the Middlesex Regiment wait to take part in a World War I centenary ceremony at the Tank Museum, Bovington, England, Aug. 4, 2014.
Stafford, England
A man looks upon the names of the dead prior to a Candlelit Vigil to mark the centenary of the First World War, at The National Memorial Arboretum in Stafford, England, Aug. 4, 2014.