Tunnel Warfare: World War One’s Secret Underground Landscape


Tunnel Warfare

The turfed up landscapes, harrowing scenes of battle, fortified strongholds, mines and barbed wire are well known features of World War One. But the extent of war digs deeper than that…. much deeper! Unknown to many, underground tunneling was a tactic used extensively on the Western Front during WW1.

Who, What, Why?

Specialist Tunneling Companies were employed to carve out a maze of tunnels and caves which would play a significant part in breaking free of the stalemate conditions experienced by soldiers fighting from trenches. Tunnels were constructed as a form of both attack and defence, using existing caves and underground facilities like catacombs for military purpose.

It was perilous work, carried out by professional miners, and often kept secret by the state, preventing the miners getting any recognition for their work.

Underneath the quaint French village of La Boisselle, runs a series of tunnels nicknamed “the Glory Hole” by British Tommies, described by historian Peter Barton as a “holy grail” for historians and archaeologists, visibly showing the “complete evolution” of trench warfare. During the Battle of the Somme in 1916, these tunnels were of significant strategic importance.

“Who goes there?”

In the twisting tunnels of these underground networks, the only way of working out the enemies location was the listen quietly for the clink of picks and shovels working away at the ground from the other side.

Bumping into the enemy could be disastrous! With no room to hide from gunfire and explosives, and the echoing walls informing both sides of any form of scuffle, confrontation was often brief. Poison gas was also used, with devastating effect, as the victims had a limited supply of air.

History repeated?

The idea of digging underneath fortifications to undermine them goes back to classical times at least, when Roman legions made use of the extensive underground aqueduct system to defend Rome against Germanic tribes, also using them to evacuate their leaders.

The addition of high explosives in WW1 added a new dimension to tunnelling as we know it. Armed with gun powder, cordite and dynamite, enemy buildings were shattered by underground explosions. During the Battle of Messines in 1917, a whopping 455 tons of explosives was deposited throughout 21 tunnels, in an operation that took over a year to prepare. It is estimated that 10,000 German soldiers were killed during this attack, during a blast so loud it was said to be heard in London.

At Spanbroekmolen, 91,111 lbs of explosives were detonated, creating a crate big enough to hold a 40ft deep lake, now known as the Pool of Peace on the Ypres Salient on the Western Front.

These sneaky attacks wore down the morale of the enemy, even if an attack had been unsuccessful. Huge craters altered the landscape in a devastating way, the effects of which can still be seen today (check out this photographer’s haunting reminder of the effects of ww2 warfare on the modern landscape)

Yet Ambush wasn’t only reason for tunnelling. These curious caves provided an opportunity for the transfer or men from one area to another, unseen and protected from the horrors of the front line.

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Written by Sarah Ashbridge

Office monkey by day, forensic archaeologist by night, Sarah Ashbridge is a jack-of-all-trades and the master of one: the forensic identification the War Dead. She trained originally as an Egyptologist, but interests in the history of death and burial saw her make the step into archaeology, completing an MSc in Forensic Archaeology and Crime Scene Investigation at the University of Bradford. Armed with an ever-increasing library of books, a handful of illustration pens and a brand new trowel, Sarah writes our regular #WWWednesday column, working towards her PhD in Forensic Archaeology.

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