Events are being held around the town of Ypres over the weekend and next week.
The main commemoration on Monday, which will be attended by Prince Charles, the Duke and Duchess of Cambridge and the King and Queen of Belgium, is taking place 100 years to the day since the battle began.
Barry Le Bailly applied for tickets in January for the national commemoration, which takes place at Tyne Cot Cemetery on Monday. More than 250,000 people applied for 4,000 tickets and Mr Le Bailly received two.
He decided to take Dave Mustow along, as his grandfather and two other relatives fought in the battle.
Tyne Cot is the largest Commonwealth War Graves Commission cemetery in the world, containing 12,000 graves and with 35,000 names of the missing engraved on its memorial wall.
‘My Jersey grandfather was François Le Bailly, who acted as a groom in the Royal Army Service Corps. I am taking a wreath with photographs of 13, and information on 23 ancestors of mine who fought. Five took part in Passchendaele, including my grandfather.’
Mr Mustow also intends to lay wreaths in memory of his two grandfathers, who both survived the war, and other relatives who did not.
While the Battle of the Somme holds a powerful place in British history, Ypres, and its surrounding settlements, such as Messines, were household names across the UK and the Commonwealth from 1914 to 1918. The destruction of this corner of Belgium by intense military bombardment that obliterated the countryside, towns and villages, resulting in the lunar-esque muddy and waterlogged landscape, came to epitomise the Great War. It was also where gas was first used as a weapon.
During the 100 or so days of the Battle of Passchendaele, between July and October 1917, an estimated 245,000 allied troops and 215,000 Germans were killed, wounded or reported missing.
