During the First World War, there was an “underground war” fought below the trenches all along the Western Front. This was very much an Engineer War fought in the tunnels of both sides. On the Canadian front, the tunnelling tasks fell primarily to the Tunnelling Companies, Canadian Engineers.
Tunnels were built for two main reasons. First, underground shelters and passageways gave protection from the violent confrontations on the battlefield. Galleries constructed off the trench systems provided shelter near the front. Troops and supplies could be moved through the tunnels to the very front wounded soldiers could be more safely evacuated. Second, tunnels took the battle to the enemy. Tunnels were dug under the German trenches, loaded with explosives, and detonated with tremendous effect in advance of an allied attack. The Canadian tunnellers were not alone. The German Army also engaged in underground operations. Occasionally contact was made and pitched battles were fought 100 feet underground.
By the fall of 1916, a vast labyrinth of tunnels had been constructed by German, French, British, Australian and Canadian Engineers in the area known as the Ypres Salient. Mount Sorrel was a 30-metre high ridge overlooking the city of Ypres. In June 1916, a major German offensive caused great damage to the Canadian defenders. German artillery and underground mining caused thousands of casualties. Nonetheless, the Canadians held out through the summer and into September. Canadian Tunnelling Companies were active and had built a significant tunnel network throughout the Salient.
On 16 September, during a German attack, a platoon of sappers of the 2 nd Canadian Tunnelling Company was busy underground enlarging the tunnel system. Vibrations felt by the men indicated that there was an artillery battle going on overhead. The platoon commander went to check the tunnel entrance for damage from shell fire. When he came up to the tunnel entrance, he found German troops occupying the position. The fight was on!
The half-mile-long tunnel system was composed of narrow passageways that were just over a metre in height and included several exits. The Germans attacked the tunnels and suffered casualties as they were forced to advance through them in single file due to the constricted space. Despite the sappers having blown all but one exit, the Germans continued to infiltrate the system.
Any show of light in the tunnels attracted weapon fire. The battle was fought face-to-face in total darkness. Sappers recognized the enemy by feeling for epaulettes on their uniforms - the Germans had them, the Canadian sappers did not. The sappers were equipped with knuckle- knives that were strapped to their wrists and made short work of any enemy they encountered. Casualties were heavy on both sides. When it seemed that all was lost for the sappers the Germans withdrew.
On the morning of 17 September, the tunnellers cautiously checked out the surface conditions. They were overjoyed to find British Tommies brewing tea. A counter-attack during the night by the Allies regained the position and the sappers could get back to their tunnelling work.
