The attack order should not have been issued. The exhausted troops were struggling through cloying black mud up Bellevue Spur.
Artillery could not reach positions where shells would provide a screen for infantry advancing on their objective. Instead the deadly barrage fell among the New Zealanders, cutting them to pieces.
German troops holding the higher ground were able to sweep the lines with machine gun fire as the hopelessly exposed units became isolated in no man's land. Wire entanglements protecting fortified enemy pillboxes remained intact, stopping the advance in its tracks and offering up easy pickings to snipers.
When the guns drew quiet, nearly 960 soldiers lay dead or mortally wounded. It took two and a half days to clear the morass of casualties. The Germans earned respect by holding their fire on recovery parties.
The work was ghastly. Hundreds of badly wounded men lay cold and scared in the waterlogged sludge. The toll included five sets of brothers. The enormous loss of life in a single Flanders day cast a pall over New Zealand.
The Western Front campaign seemed in the weeks which followed a futile effort, the sacrifice of human life out of all proportion.
Passchendaele does not yet occupy the same solemn place as Gallipoli and Anzac Day in the nation's collective memory. But over the last 10 years the New Zealand and Flemish Governments have taken a number of initiatives under the Ypres Agreement to honour the war dead, educate younger generations about the tragedy and give the sorrowful events an appropriate place in our commemorative calendar.
The most tangible sign of this investment is taking shape in the form of a memorial garden, which is being constructed in New Zealand. It will be shipped to Belgium and laid out in the shape of a poppy alongside similar gardens installed by the other nations who lost men in the battles.
The garden will be completed in time for the centenary of Passchendaele, finally a place of peace where far too many young New Zealanders died in the horror of war.