Full coverage of the commemorations marking 100 years since the Battle of the Somme
The Battle of the Somme was fought between 1 July and 18 November 1916, with over a million British, French and German casualties
1 July 1916 remains the bloodiest day in British military history with 57,470 casualties, 19,240 of whom were killed
The centenary was marked by a national two minutes' silence at 07:28 on 1 July, the moment soldiers went over the top
Let us know about your commemorations using #Somme100
History of World War One
This flag flew above the base camp of the 36th Ulster Division, and still bears the scars of artillery fire.
See more objects from the Battle of the Somme and the Easter Rising on BBC Voices 16, external.
Battered on the battlefield but now placed with pride in Belfast's Ulster Museum.
The 600 UK, Irish and French schoolchildren involved in the commemorations at the Thiepval memorial were part of an educational programme organised by the British Council.
Earlier the Duke and Duchess of Cambridge were presented with a collection of art, photography and history work produced by the pupils as they toured a new visitor centre at the site.
Relics from the trenches displayed under a glass floor, include shell cases, barbed wire, boots and horseshoes.
Image source, Reuters
Image source, Getty ImagesHistory of World War One
The men who went over the top on 1 July had not necessarily viewed their mission as a death sentence. On the night before the attack, Second Lieutenant Percy Boswell wrote: “I am absolutely certain that I shall get through alright but in case the unexpected does happen, I shall rest content with the knowledge that I have done my duty and one can’t do more.”
Percy Boswell was killed on the first day of the Battle of the Somme, aged just 22.
Dan Snow reads the final letter of Second Lieutenant Percy Boswell
Of the five Scottish battalions moving off at "zero hour" on 1 July 1916, four of them were made up of friends and workmates recruited from Edinburgh and Glasgow.
All would suffer heavy casualties, but probably the worst affected was the 16th Highland Light Infantry (the Boys' Brigade battalion).
Image source, Crown
Image source, Getty ImagesWatch, external historian Dan Snow explain the importance of one of the most notorious battles of World War One.
History of World War One
You can see the original Battle of the Somme film, with Laura Rossi’s acclaimed score commissioned by the Imperial War Museum.
Find a screening near you, external
Image source, Imperial War MuseumScene from the Battle of the Somme film
In 1916, the Battle of the Somme film was seen by nearly half the population of Britain.
BBC iWonder: Why was the Battle of the Somme film bigger than Star Wars?, external
Schoolchildren from the UK, Ireland and France laid wreaths at the graves beside the Thiepval Memorial during the service.They were later greeted by the Duke and Duchess of Cambridge, prime minister and other dignitaries.
Image source, EPAHistory of World War One
The Royal Dublin Fusiliers was made up of recruits from Dublin and the surrounding Irish counties. The men were professional soldiers from the British Expeditionary Force (BEF).
Image source, IWMCap badge of the Royal Dublin Fusiliers.
At 09.00am 503 soldiers advanced under heavy fire from Beaumont-Hamel. Five minutes later orders came through postponing the attack, C and D companies were halted, but the rest of the battalion were trapped in no-man’s land.
At lunchtime, the men were ordered to retreat and defend the British front line from German counter attacks.
Out of 503 men, 325 were casualties.
Image source, IWMCardinal Francis Bourne inspecting troops of the 8/9th Battalion, Royal Dublin Fusiliers at Ervillers, 27 October 1917.
The BBC Symphony Orchestra played The Banks of Green Willow by composer George Butterworth while wreaths were laid at the Cross of Sacrifice by Prince Charles, President of Ireland Michael D Higgins, UK Prime Minister David Cameron, former President of the Federal Republic of Germany and Vice Admiral Tim Laurence.
Butterworth served with the 13th Durham Light Infantry and was killed in action on 5 August 1916.
Children from the UK, Ireland and France then lay floral tributes on each grave at the cemetery.
Image source, bbc
Image source, PAThe Duchess of Cambridge has told British and French schoolchildren she is finding her visit to the Somme "emotional".
Speaking at a new visitor centre at the Lutyens-designed Thiepval Memorial to the Missing of the Somme, she told children it was "very moving" to be there.
Prince Harry also spoke to children there, telling students from St Paul's Community College in Waterford, Ireland, and Wolsingham School in County Durham: "It's important that you are here. There are all sorts of parts of history that are being forgotten.
"It's important for us to remember older history as well as more recent history."
History of World War One
Image source, IWMAlbert Tattersall took this cigarette tin with him to the Battle of the Somme. He and his brothers John and Norman were part of a Pals battalion in the Manchester Regiment.
During the afternoon of the 1 July, the battalion went over the top near Fricourt. The attack was unsuccessful and Albert was wounded and taken to a casualty station. He died of his wounds two days later, and his personal effects were sent home to his parents in Manchester.
628 Victoria Crosses were awarded during World War One. Today, five ceremonies are taking place to remember those who received crosses for their brave actions on 1 July 1916. Specially designed paving stones will be laid near their place of birth, as part of a four-year project to honour recipients.
The Archbishop of Canterbury Justin Welby read a prayer which had been written for the commemoration to remember those who fought and lost their lives.
He said:
Quote MessageWe recall with thanksgiving the nobility of spirit, the loyalty shown to comrades, and the struggle of those facing their fears - the courage of those who daily faced the trauma of battle. May we never forget the devastating loss of this battle, the pain of those on the home front, and the sacrifices that were made.
Archbishop of Canterbury
Vice Admiral Sir Tim Laurence - vice chairman of the Commonwealth War Graves Commission - read For the Fallen, by Laurence Binyon, before the Last Post was played ahead of a two-minute silence.
As the crowd fell silent, red and blue petals fell from the top of the memorial building.
Today Programme
BBC Radio 4
Six hundred British, Irish and French school children are visiting the Thiepval Memorial to remember those who died in the battle of the Somme.
Some of them spoke to Radio 4's James Naughtie about the connection they still feel with those who fought in the war 100 years ago.
At Manchester Cathedral thousands are marking the centenary of the Battle of the Somme with a remembrance service and a parade.
Danny Savage is there taking your questions, live, on the BBC's Facebook page.
Put your questions to him in the comments section of the page, which you can find here, external.
The Prince of Wales has read a description of Thiepval, as written by John Masefield, in 1917.
As he read from The Old Front Line, rain continued to fall on the thousands gathered there.
Those present then joined together to sing Abide with Me - known to have been sung by troops on the battlefield.
Students from Severn Vale Academy read a poem in memory of the Somme.
One hundred years since the Battle of the Somme, students from Severn Vale Academy read the poem "On Somme" by Ivor Gurney on the banks of the River Severn.
History of World War One
Surviving soldiers had the grim task of dealing with the corpses of their fallen comrades. This handwritten letter, written on 1st July, gives orders on how to bury the dead.
See more objects from the Battle of the Somme and the Easter Rising on BBCVoices 16, external.
Today Programme
BBC Radio 4
The Archbishop of Canterbury says when he looks at the memorial to the dead from the Battle of the Somme he thinks of a "catastrophic political failure".
Justin Welby spoke to Radio 4's James Naughtie at the Thiepval memorial as commemorations got under way, with the band of the Welsh Guards playing in the background.