- Video report by Senior International Correspondent John Irvine
A memorial service has been held in Belgium to pay tribute to the thousands who lost their lives on the Battle of Passchendaele centenary.
Prince Charles, the Duke and Duchess of Cambridge and Prime Minister Theresa May attended the ceremony at Tyne Cot cemetery near Ypres.
The King and Queen of Belgium and relatives of those that died in the Third Battle of Ypres conflict were also in attendance.
Almost 54,000 British men did not return home from the Belgian battlefields.
Addressing the gathering, the Prince of Wales spoke of the sacrifice and "bravery" of those killed.
"We remember it not only for the rain that fell, the mud that weighed down the living and swallowed the dead, but also for the courage and bravery of the men who fought here."
"Drawn from many nations, we come together in their resting place, cared for with such dedication by the Commonwealth War Graves Commission, to commemorate their sacrifice and to promise that we will never forget," Prince Charles added.
The bloody First World War conflict was fought in the summer and autumn of 1917 and thousands of British, Allied and German soldiers lost their lives.
Between July 31 and November 10 there were more than half a million casualties - 325,000 Allied soldiers and 260,000 to 400,000 Germans.
The ceremony also included the Calling Of The Names, personal stories of some of the thousands of British and Commonwealth soldiers and others present at the battle.
Prince William completed the Calling Of The Names by reading that of the Unknown Soldier, saying he was "A soldier of the Great War, known unto God."
They also included a letter written by a German soldier.
Prince Charles and King Philippe then led the laying of wreaths at the cross of remembrance.
On Sunday, the prince spoke at the Menin Gate monument and also paid tribute to the many "who sacrificed everything for the lives we live today."
He added: "During the First World War Britain and Belgium stood shoulder to shoulder. One hundred years on, we still stand together, gathering as so many do every night, in remembrance of that sacrifice."
The Menin Gate in the Belgian town is covered with the names of 54,391 British dead who have no known grave.
The poet Siegfried Sassoon's summed up the conflict with the line "I died in hell, they called it Passchendaele".