By Dominic Hughes
BBC News, Europe reporter
With its rows of white Portland Stone headstones and beautifully tended graves, Tyne Cot Cemetery is a place of peace and tranquillity.
The largest of the many Commonwealth War Graves cemeteries that lie dotted around this part of Belgium, it is the final resting place of nearly 12,000 soldiers.
Tyne Cot is the Commonwealth's largest war cemetery
The names of another 35,000 soldiers whose remains were never found or identified line the memorial wall at the back of the cemetery - from the Lancashire Fusiliers, the Argyll and Sutherland Highlanders, even the Postal Office Rifles.
They came from throughout the United Kingdom and what was then the British Empire - the Anzacs of Australia and New Zealand, Canadians and South Africans.
But whether from Britain or further afield, their journey ended here, in the mud of Flanders.
'Slimy water and dead bodies''
Ninety years ago, the battle of Passchendaele claimed the lives of around half a million soldiers on both sides, and came to symbolise the full horror of warfare on an industrial scale.
The battle of Passchendaele was in fact a series of battles, fought across fields that had become a potentially deadly quagmire of liquid mud.
A massive bombardment of German lines combined with heavy rain created appalling conditions.
The journalist Philip Gibbs, writing in 1923, described the battles fought here as "the most awful, the most bloody... the most hellish heavy rains fell, and made one great bog in which every crater was a deep pool...they were like lakes in some places, filled with slimy water and dead bodies."
It's hard to imagine those scenes now. The fields below Tyne Cot cemetery are now planted with potatoes and sweetcorn in this quiet, rural corner of Belgium.
But the reminders of the Great War are everywhere, from the memorials and cemeteries to odd features in the landscape - the faded lines of the long-gone trenches or the remains of a massive crater where the fighting left its mark.
Today Tyne Cot was busier than normal. Members of veterans associations, young cadets and relatives of long dead soldiers gathered to join the Queen, the Duke of Edinburgh and Queen Paola, Queen of the Belgians, to commemorate the 90th anniversary of Passchendaele.
Mr Mason, Mr Atkinson and Mr Armstrong were among the veterans at the commemoration
Among the crowd were Alfred Mason, 83, Dick Atkinson, 87, and Colin Armstrong, 73, all of the Durham Light Infantry Association.
They travel once or twice a year to remember fallen comrades.
Mr Atkinson marched near here in 1944 after D-Day.
Despite being injured when he landed on the Normandy beaches he was back fighting within weeks.
The ceremony itself was a mix of prayer and hymns, as well as testimony from young relatives of two British soldiers who died at Passchendaele.
Father and son died
Rupert Forrester, 18, spoke of Harry Moorhouse, his great great grandfather, and his great uncle Ronald.
Father and son served together in the same regiment, both being decorated for bravery.
But both died within an hour of each other.
"In a way I'm glad of the time they were able to spend together here," said Rupert.
The Queen and Belgium's Queen Paola paid tribute to the war dead
Also in attendance were UK Defence Secretary Des Browne, Scotland's First Minister Alec Salmond and the new Deputy First Minister for Wales Ieuan Wyn Jones.
Also there were the High Commissioners for New Zealand and Australia as well as Ministers from Canada, and ambassadors from France, Germany and Ireland. And there was an international flavour too as a New Zealand Choir sang the traditional song for soldiers leaving for war.
"Now is the hour, when we must say goodbye. Soon you'll be sailing far across the sea. While you're away, please remember me. When you return you'll find me waiting here."
The number of soldiers whose names are inscribed on the Portland stone of Tyne Cot cemetery are a reminder of how many never made that journey home.