The sun has set at Buttes New British Cemetery in Belgium, where 1000 people have convened to commemorate New Zealand's darkest day.
In three short hours on October 12, 1917, New Zealand suffered 2735 casualties during the Battle of Passchendaele.
It would become the nation's greatest loss in a single day.
The objective on the day had been to capture Bellevue Spur, but as the troops surged into waist-deep mud they were caught on uncut barbed wire while German machine guns rained down on them.
Gavin Leckner's grandfather, Theodore Ernest Leckner, was one of the 843 men who died in the battle 100 years ago.
He was 28, and his grave is unknown.
Mr Leckner and wife Helen travelled from Red Beach, on the Hibiscus Coast, to attend the special musical service on Thursday, held at one of the many Commonwealth War Grave Cemeteries just outside of Ypres, Belgium.
"Grandma never talked about it," Mr Leckner told NZ Newswire.
"I knew that he'd been killed in the war. In my later years I became more and more interested."
Theodore Leckner left Ward, Marlborough, for war with the Canterbury Regiment in 1915, leaving behind a wife and seven children with another one on the way, Mr Leckner's own father.
On Thursday, as the sun set over the cemetery and the surrounding Polygon Wood, the New Zealand Defence Force band and Maori cultural group performed Aroaroa, capturing the suffering of those at the battle as well as those waiting at home.
Earlier on Thursday, the Duke of Cambridge, representing Queen Elizabeth II, along with Belgium's Princess Astrid, joined more than 2000 people at the nearby Tyne Cot Cemetery, the resting place of 512 Kiwis.
"Half a world away, news of the losses was felt like a shock wave - every death here left a shattered family there," Prince William said of the battle now synonymous with the horror of WWI.
"No part of New Zealand was untouched by loss."
This is true for the Leckner family.
Mrs Leckner's great uncle, Stanley Arthur Ambrose Saint, also died in the Flanders region, at the Battle of Messines several months before Passchendaele.
A note to Mr Saint's father from a fellow soldier describes how, exhausted after being awake for 36 hours, he'd been killed by a "Hun shell" as he slept.
"He was buried in the line the same day with another Levin boy named Sciascia," the note reads.
Mr Leckner said two of his great uncles also died in the Flanders Region.
In the month the New Zealand Division was engaged in Passchendaele campaign, about 1900 soldiers died and another 4100 were wounded or evacuated sick.
"I sometimes wonder how the world would have been different if all those people hadn't died," Mr Leckner said.
"What they would have achieved."