Mining history by Harold Hough

When we think of top secret military units, we usually think of the Seals, Green Berets, and other Special Forces. However, in World War One, one of the most secret military units in the British Army consisted of Welsh miners. The unit was so secret that other soldiers were unaware of their existence and when these miners died during operations, the families weren’t even told how and where they died. In many cases, these brave miners remain in unmarked graves under the soil of Flanders and France.

A hundred years ago, in the autumn of 1914, the battle lines on the Western Front had stabilized and a network of German and Allied trenches ran from the Swiss border to the English Channel. No man’s land was crisscrossed with barbed wire and swept by machineguns. To charge across hundreds of yards of such terrain was suicide.

It was the Germans who first came up with the idea of tunneling underground to destroy part of the enemy’s trenches. On December 21, 1914, they set off 10 landmines in the trenches of a British-Indian unit. But, the British were quick to respond. Within weeks they had formed the first tunneling companies and a year later they had 25,000 trained tunnelers, mostly raised from coal mines in Wales.

Although the first tunnelers were recruited from sewer digging firms, the Army soon realized they needed more experienced men. The soil of Flanders covered a layer of unstable sand and then clay and chalk. In order to dig deep enough to reach the safer clay and chalk layers and to make the tunneling effort harder to detect, they needed professional miners who could dig tunnels over 80 feet deep and keep them free of water and poisonous fumes.

This was where the Welsh coal miner was ideal. Not only was he comfortable working underground, he was known for his work ethic and was usually shorter and more muscular than the average Englishman. In fact, during the patriotic rush to join the Army in the early days of the war, many miners were turned down for being too short (the minimum height requirement for the British Army was 5’ 3”) or too old. Now coal miners under the height requirement and up to 60 years old were in great demand.

Although tunneling under German trenches was a dangerous business, the members of these tunneling companies didn’t get any public accolades for their work. In fact, their work was highly secret. Troops not directly involved in tunneling (including attached infantry) were not told about any mining effort because it took so long to complete a tunnel – well over a year for the Messines offensive. Any leak of intelligence to the Germans on a tunneling effort would mean the loss of a lot of time and energy. It would also probably force the cancellation of a planned offensive.

Another reason for the secrecy was what could happen if the enemy did discover the tunnel. The best method for destroying a tunnel was to build a counter-tunnel that would come close to the first tunnel and then be loaded with explosive and set off. This not only destroyed the original tunnel, but would often leave the miners trapped to die from entombment, drowning, gassing or bleeding to death in cramped and claustrophobic galleries beneath no man’s land.

In some cases, the enemy miners would unexpectedly break into each others tunnels and fierce hand to hand combat with knives, shovels, and pickaxes would ensue.

The Battle of Messines

Despite the dangers, these tunnels proved valuable to the war effort. In fact, one of the most successful operations of the war, the Battle of Messines, couldn’t have been won by the British Army without the effort of the Welsh miners.

The target of the offensive was the Messines Ridge, a natural stronghold southeast of Ypres in Flanders. The general in charge, General Plummer was a cautious man who wanted to limit British casualties. About 18 months before the battle, he had authorized the laying of 22 mine shafts underneath German lines all along the ridge. His plan was to detonate all 22 at one time - followed by infantry, heavily supported by the use of artillery bombardments, tanks and the use of gas.

Despite heavy German counter-tunneling, British miners were able to dig 8 kilometers of tunnels and lay 600 tons of high explosives by the day of the attack. One tunnel was destroyed by German counter-tunneling and hand to hand combat between German and Welsh miners.

Although the Germans were expecting an attack and were in their defensive positions, they didn’t expect what would happen next. 19 tunnels exploded simultaneously with a blast that was heard in Dublin, Ireland and No. 10 Downing Street in London. 10,000 Germans were killed instantly and the stunned ones were left to face 9 British divisions that moved forward. In a war where offensives could take months and where gains were frequently measured in yards, The British reached their final objectives by mid afternoon.

But, the victories of WW I had a high price. Hundreds of miners died in the tunnels, their bodies often unrecoverable. Since the tunneling operations were so secret, the families were merely told that they had died, but weren’t told how or where. And, since many were killed deep underground, there was no grave – only a name of a memorial.

There was, however, a long term benefit to the mining industry. In 1915, the Royal Engineers formed a mine rescue school to train soldiers and miners in mine rescue. The school also designed and tested mine rescue equipment, including breathing apparatuses. Much of this work would finally find its way back to the mining industry.

The value of what these miners did was noted by one of the most important field commanders of the war. Writing at the end of 1916, Field Marshal Haig, commander of British forces on the Western Front, noted: “The Tunneling Companies still maintain their superiority over the enemy underground, thus safeguarding their comrades in the trenches…Their skill, enterprise, and courage have been remarkable.”

P.S. If you have been counting the number of tunnels mentioned in the article, you probably have noticed that two tunnels at the Battle of Messines are unaccounted for. For some reason they didn’t explode and their location was lost. One of the mines was detonated in a thunderstorm on June 17, 1955: the only casualty was a dead cow. The second mine remains undetected nearly a century later.