First world war soldiers leave their mark with graffiti found in Naours, France

A headlamp cuts through the darkness of a rough-hewn passage 30 metres underground to reveal an inscription: "James Cockburn 8th Durham L.I."

It's cut so clean it could have been left yesterday. Only the date next to it - April 1, 1917 - roots it in the horrors of the first world war.

The piece of graffiti by a soldier in a British infantry unit is just one of nearly 2,000 century-old inscriptions that have recently come to light in Naours, a two-hour drive north of Paris. Many marked a note for posterity in the face of the doom that trench warfare would bring to many.

"It shows how soldiers form a sense of place and an understanding of their role in a harsh and hostile environment," said historian Ross Wilson of Chichester University in Britain.

Etchings, even scratched bas-reliefs, were left by many soldiers.

But those found in Naours "would be one of the highest concentrations of inscriptions on the Western Front" that stretches from Switzerland to the North Sea, said Wilson. The site's proximity to the Somme battlefields, where more than a million men were killed or wounded, adds to the find's relative importance.