It distressed Aurel Sercu, a humane man, that he could not put a name to the man. "I wish that one day we can get directly in touch with relatives or descendants. And I can tell them 'Look, we found the remains of your grandad and his dog-tag and his spoon and a rifle.' That would be a very touching, moving moment, I suppose."

Sercu, a retired schoolteacher, belongs to a group of amateur Belgian archaelogists who call themselves The Diggers. Their work is slogging spadework and the soldiers of the first world war would recognise it. When excavators, building an industrial estate outside Ypres, turned up evidence of battle, The Diggers struggled to keep ahead of the bulldozers. ("Every Saturday we are here, rain or shine, winter or summer, we are here.") What they found astounded them, an intact sector of the western front. Trenches, dugouts, ammunition, poison gas, a broken bayonet marked "Wilkinson" and hand grenades marked AEG. A golden wedding ring and a bottle of HP Sauce.

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Then they began to find bones and skulls and boots with feet in them. Their shocked silence was quite different to the usual larkiness of pop archaeology. They called the police in case it was homicide, which it was. They found 125 bodies, all nameless. The Welsh fusilier was the last and most complete. Nationality could be established easily from their regimental insignia, but identity was encoded in their DNA.

The British went over the top here on July 6, 1915. The battle was bloody and inconclusive. The British Commander, General Plumer, said "Splendid achievement... complete success... will go down in history as one of the great battles of the campaign." In fact, it was wholly forgotten.

"What we learn from this", said Aurel Sercu as the dead were reburied, "is that we never learn."