Archaeologists have begun the most detailed ever study of a Western Front battlefield where 28 British tunnellers lie beneath untouched scrubland, entombed victims of a “hidden” underground war.
But they could do nothing until the French family who has owned the land since the 1920s, decided to open it up to research last May.
Mr Jones, a former curator at the Royal Engineers Museum, said the dig was crucial to complete the stories of the 179th and 185th Tunnelling Companies who worked at the Glory Hole, as they called it.
“Although we know a great deal about the lives of soldiers in World War One, these men have left very few clues as to their experience or feelings,” he said.
Through war diaries, tunnel plans and records, Mr Jones has identified 25 of the 28 British and all 10 French tunnellers at the site. The number of Germans remains unclear.
One victim was Sapper John Lane, 45, from Tipton in Staffordshire, a married father-of-four killed along with four others 80ft underground on 22 November 1915.
His great grandson, Chris Lane, 45, from Redditch in Worcestershire, said he had been gripped to learn about his relative’s fate.
“It’s important to know your past, one small incident for one family is history for lots of other people,” he said.
Archaeologists and historians from Britain, France and Germany intend to preserve the area as a permanent memorial to the fallen. As sapping was long a state secret, the men did not get the recognition they deserved at the time.
The task of mapping the tunnels and trenches with ground penetrating radar has begun, with digging due to start in October.
Some open tunnel sections have already been inspected and are remarkably well preserved.
Researchers intend to leave the bodies undisturbed in the collapsed tunnels, but any others found in trenches will be reburied in accordance with the Commonwealth War Graves Commission.
Bomb disposal experts will be at hand to defuse the probably abundant unexploded ordnance they come across.