Men of the German 148th Infantry Regiment in a tunnel 15m below ground in the Champagne area in 1917. It is a typical German accommodation and communication tunnel and is reminiscent of the Cornillet tunnel, in which over 300 Germans were trapped and poisoned on 19–20 May 1917 during the Third Battle of Champagne. Like the Cornillet system, these tunnels were electrically lit, with signals cables running along the roof, and a light railway truck. (Author).