Solemn memorial services and commemoration vigils have been held across Europe on Friday (1 July 2016) to mark the 100-year anniversary of the start of the Battle of the Somme. Often called the Somme Offensive, the battle began on 1 July 1916. By the time it finished on 18 November of that year, British, French and German casualties numbered more than 1,250,000 men. It is considered to be one of the bloodiest battles in history.

Somme Commemoration
French soldiers attend a commemoration event during the 100th anniversary of the beginning of the Battle of the Somme at the Thiepval memorialPhil Noble

The main memorial service was held at the Thiepval Memorial in northern France on Friday. Beginning to the sound of cannon shots, the ceremony saw 600 British and French children laying down a flower crown on the 600 British and French graves of the cemetery. Ahead of the commemoration, guests were given special newspapers that told the stories of many who died during battle.

"[4 September, 1916]

Dear Jim,
Received yours dated August 27th. Yes I got the parcel safe. We haven't half been getting put through it lately. We have now been in [crossed out] out of the line about 3 weeks but we are training heavy to take part in the push & I am only wishing the war was finished before we go up, but no such luck, never mind I'll just have to take my chances as all the other boys."

Guests and dignitaries, including French President Francois Hollande, UK Prime Minister David Cameron and Prince Charles read from texts, describing scenes from the front line in 1916. French, British and Irish songs inspired by the war were sung.

Somme Commemoration
British horse guards stand guard as they take part in the memorial ceremony at the Franco-British National Memorial in Thiepval on 1 July 2016Stephane de Sakutin
Somme Commemoration
A woman reads a reprinted newspaper ahead of the Commemoration of the Centenary of the Battle of the Somme at the Thiepval Museum ahead of the 100th anniversary of the beginning of the Battle of the SommeChris Radburn
Somme Commemoration
School children hold wreaths as they attend a commemoration event at the Thiepval memorial to mark the 100th anniversary of the Battle of the SommePhil Noble/Reuters
Somme Commemoration
French guards at a service to mark the 100th anniversary of the start of the battle of the Somme at the Commonwealth War Graves Commission MemorialChris Radburn
Somme Commemoration
A floral tribute left on a wall ahead of the 100th anniversary of the beginning of the Battle of the Somme at the Thiepval memorial to the MissingYui Mok
Somme Commemoration
Prince William and Catherine, Duchess of Cambridge speak with French officials as they arrive in ThiepvalFrancois Mori/AFP
Somme Commemoration
The Kings troop Royal horse artillery attend a commemoration event at the Thiepval memorial to mark the 100th anniversary of the Battle of the SommePhil Noble
Somme Commemoration
Catherine, Duchess of Cambridge attends a service to mark the 100th anniversary of the beginning of the Battle of the Somme at the Thiepval memorial to the missingYui Mo
Somme Commemoration
(left-right) French President Francois Hollande, Prince Charles, Prince of Wales, Camilla, Duchess of Cornwall, Prime Minister David Cameron, Irish President Michael D. Higgins and his wife Sabina Coyne during the serviceAndrew Matthews

Many relatives of soldiers wore poppies and cornflower pins – the British and French symbols to remember those who died were also in attendance. Members of the royal family attended the ceremony, including the Duke and Duchess of Cambridge, Prince Harry and the Duchess of Cornwall also attended the ceremony, along with Irish President Michael D Higgins and former German president Horst Koehler.

Somme Commemoration
French soldiers (left) and British horse guards stand guard as they take part in the memorial ceremony at the Franco-British National Memorial in ThiepvalStephane de Sakutin
Somme Commemoration
Prince Harry, Catherine, Duchess of Cambridge and Prince William, Duke of Cambridge during the service to mark the 100th anniversary of the beginning of the Battle of the Somme at the Thiepval memorial to the missingPhil Noble
Somme Commemoration
French President Francois Hollande, Prime Minister David Cameron, Prince William, Duke of Cambridge, Catherine, Duchess of Cambridge and Prince Harry greet guestsChris Radburn
Somme Commemoration
Prince William, the Duke of Cambridge and his Catherine the Duchess of Cambridge, visit the Thiepval monumentFrancois Mori/AFP
Somme Commemoration
France's President François Hollande and Prince William unveil a commemorative plaque inside the Thiepval monumentFrancois Mori/AFP
Somme Commemoration
Catherine, Duchess of Cambridge, during a ceremony at the Thiepval MemorialPhil Noble
Somme Commemoration
People carry poppy wreaths ahead of the 100th anniversary of the beginning of the Battle of the Somme at the Thiepval memorial to the missingYui Mok
Somme Commemoration
UK Prime Minister David Cameron prepares to lay a wreath during a ceremony at the Thiepval MemorialFrancois Mori
Somme Commemoration
Camilla, Duchess of Cornwall, (centre) attends the memorial ceremony at the Thiepval MemorialStephane de Sakutin

Other commemorations have taken place, with Westminster Abbey holding two vigils, one on the eve of the Somme and the other on the anniversary. Soldiers paid their respects at the Lochnagar Crater, a mine crater dug in the front line that spans 91m wide and 21m deep. Commuters across the UK were met by young men dressed in vintage uniforms, who sat, stood and wavered among the crowds at railway stations. Many sang wartime songs, while others handed out cards bearing the names of the soldiers killed on the first day of the battle and the hashtag #wearehere.

Somme Commemoration
Prince Charles (right) and British Prime Minister David Cameron attend the ceremony at the Thiepval MemorialFrancois Mori
Somme Commemoration
Men dressed as World War I soldiers take part in the memorial ceremony at the Franco-British National Memorial in ThiepvalStephane de Sakutin
Somme Commemoration
A message on a Poppy outside the Thiepval Museum ahead of the 100th anniversary of the beginning of the Battle of the Somme at the Thiepval memorial to the MissingChris Radburn
Somme Commemoration
French President Francois Hollande, Britain's Prince William, Britain's Prime Minister David Cameron, Britain's Princess Catherine, Britain's Prince Charles, Britain's Prince Harry and Britain's Princess Camilla walk towards the Thiepval MemorialFrancois Nascimbeni/AFP
Somme Commemoration
French soldiers stand in line during the 100th anniversary of the beginning of the Battle of the Somme at the Thiepval memorial to the missingPhil Noble
Somme Commemoration
Scotland's First Minister Nicola Sturgeon smiles as she waits to take a seat at the Commemoration of the Centenary of the Battle of the SommeAndrew Matthews
Somme Commemoration
The Kings troop Royal horse artillery line up during the 100th anniversary of the beginning of the Battle of the Somme at the Thiepval memorial to the missingPhil Noble
Somme Commemoration
Labour Party leader Jeremy Corbyn waits to take a seat at the Commemoration of the Centenary of the Battle of the SommeAndrew Matthews
Somme Commemoration
People arrive ahead of the Commemoration of the Centenary of the Battle of the SommeChris Radburn