AT 7.28am on Saturday, July 1, 1916, the morning of the first day of the First World War Battle of the Somme, the biggest man-made explosion the world had ever seen erupted beneath the front line of the German Army.

Just south of the village of La Boisselle in northern France the ground shook as 27 tons of ammonal were detonated in an ear-splitting roar that sent a column of earth nearly a mile into the sky and left a crater 90ft deep and 100 yards wide.

Eye witness 2nd Lieutenant Cecil Lewis of the Royal Flying Corps was later to write: “The whole earth heaved and flashed and a magnificent column rose up higher and higher to almost 4,000ft.

"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.”

Beneath it hundreds of German soldiers lay dead or dying.

Fast forward to the spring of 2011 and in a little workshop next to his house in the village of Crowle, near Worcester, wood carver Tim Rogers is deep in concentration.

Chips fly from a block of lime as he taps a chisel with a mallet on his way to creating another masterpiece. Currently Tim is carving a wooden model of a wreath of poppies.

This will one day hang at the entrance to Lochnagar crater, the name given to the hole gouged into the earth by that huge explosion in 1916 and which is today preserved as a war memorial.

A teacher by profession, Tim took early retirement and since the late 1990s has been visiting the Great War battle sites in France and Belgium. It was in 2005 he first set eyes on the massive scar at Lochnagar.

He said: “I had never seen anything like it. To think it had been caused by human hands was almost unbelievable.”

What had happened was that a team of tunnellers, working off a front line British trench called Lochnagar Street, first dug a shaft 90ft down into the chalk soil and then set off towards the German lines. In a quite remarkable feat of underground engineering they excavated a tunnel 300 yards long and at the end of it built two large chambers 60ft apart. Into these were packed 60,000lbs of explosives, all of which, obviously, had to be carried along the tunnel. In fact the chambers were deliberately overcharged.

The quantity of ammonal was designed not just to break the surface and kill in the immediate area but also to cause spoil to fall in the surrounding fields and form a lip around the crater. This lip, which ended up 15ft high, acted as protection for the advancing British troops against machine gun fire from German positions in La Boisselle.

The whole saga of Lochnagar Crater has given fresh focus to Tim’s woodcarving skills, which he has inherited from his father and which have filled his home with models of everything from galloping horses to crouching cats.

He said: “My father was a master craftsman, a cabinet maker who specialised mostly in furniture. Exact fits were his speciality, especially joints. He gave my brother and I rudimentary woodworking skills, how to use chisels etc, and I grew up with those sort of tools about the house. In fact I always wanted to be a stonemason but my mother insisted I had a more reliable job with a pension. That’s why I went into teaching.”

However, a career in the classroom didn’t prevent Tim being a “weekend woodworker” and he has continued to carve over the years using just about every subject and probably every kind of wood. Examples of his talent can be found inside the door of Crowle Parish Hall, where he has contributed a 6ft by 3ft carving of scenes of village life.

Everything, no matter what the final appearance, starts out as a solid block of wood.

Tim said: “You might have an idea of what you want to do when you begin but as you go along you have to negotiate with the wood over what is possible. With its grains and its knots and its blemishes, the wood talks to you.”

His experience on seeing Lochnagar Crater for the first time so moved him, Tim has now joined an organisation of Friends,which helps maintain the crater. The site is owned by Englishman Richard Dunning, who bought it in 1978 and preserves it as a garden of remembrance to those from all nations who suffered in the First World War.

As well as his wreath of poppies, Tim has carved several models with Lochnagar connections, such as a set of Tommies on the battlefield called Hole in the Wire and a group of three soldiers, German, French and British, as a symbol of reconciliation. On the same theme, there are three converging hands.

Finally, should anyone ever doubt the significance of the Great War, and in particular the Battle of the Somme, to the countries of Europe, consider this. The 100th anniversary of July 1, 1916, is due to be marked by a series of special events.

Already every hotel and guest house room within a day’s march of Lochnagar is taken. And there are still five years to go.