First World War: The blast was heard in London as mine exploded, leaving a huge scar in the French countryside

A great scar in the rolling countryside of northern France, the crater is a reminder of the destruction wrought as the great European powers slugged it out in “the war to end all wars”.

This year we mark the 100th anniversary of the outbreak of that war and the crater remains a stark physical reminder of the power of industrial conflict – it is the largest man-made mine crater created in the First World War on the Western Front.

The mine was laid by the British Army’s 179th Tunnelling Company Royal Engineers underneath a German strongpoint called “Schwaben Höhe”. Though exactly where the tunnel was has been lost in the mists of time.

The mine was exploded two minutes before 7.30am – Zero Hour at the launch of the British offensive against the German lines – on the morning of July 1, 1916 and the explosion could be heard as far away as London.

A witness described the scene: “The whole earth heaved and flashed, a tremendous and magnificent column rose up in the sky.

“There was an ear-splitting roar drowning all the guns, flinging the machine sideways in the repercussing air.

“The earth column rose higher and higher to almost 4,000 feet. There it hung, or seemed to hang, for a moment in the air, like the silhouette of some great cypress tree, then fell away in a widening cone of dust and debris.”

Now in private ownership, the crater is found just outside the village of La Boiselle.

It is maintained by the Friends of Lochnagar who give up their spare time to look after the site and help preserve it as a memorial.

On the day I visited, 83-year-old Leslie Disbrey talked to me about what the crater means to him.

He said: “My uncle Herbert Disbrey was last seen alive on the first day of The Somme on Fricourt Ridge not far from the crater. He was a private and joined up as a volunteer in 1914 in the 11th Battalion Suffolk Regiment. His body was never found but he is commemorated at Thiepval.”

Today the crater is dedicated to peace, fellowship and reconciliation between all nations who fought on the Western Front.

Leslie added: “I came out here with my cousin in 1976 for the 60th anniversary of the battle. Ever since someone from the family has come here every year. The crater is a way of remembering and preserving the memory of those who died.”

Richard Dunning bought the crater in 1978 to ensure its survival.

He said: “Every year we hold a remembrance ceremony on July 1. I view the crater as a physical reminder of the horror of war and it is also a living wound in the landscape which represents the suffering and sacrifice of those who were here.”