This story originally appeared in the August 2014 issue of National Geographic magazine as "The Hidden World of the Great War ... of the trenches above. A journalist visiting one of the caverns ...

On every front—political, economic, technological, social, spiritual—World War I was changing ... Archives of American Art, S.I. Life in the trenches, wrote the British poet Siegfried Sassoon ...

That was - historian Andy Robertshaw insists - the experience of most soldiers in the First World War. It was not one of constant fighting, never-ending trench foot and heartless aggression from ...

Military historian and World War One enthusiast Brian Kenny is so dedicated to the cause that he single-handedly dug a trench in his back yard to recreate the conditions endured by so many in ...