This Explosion Was the Biggest Blast Before Atomic Bombs

On a calm, cool evening in early June 1917, British Major General Charles Harington gathered with a group of reporters on the Western Front to discuss a massive attack that would be launched soon against German forces. Rumors had been drifting for weeks of a major offensive planned near the Belgian town of Messines, and the reporters were eager for details.

By that point, three years into Europe’s ghastliest conflict, neither the British nor their allies had made much progress against the enemy. The Germans, likewise, had failed to land a decisive blow. Armies on both sides were drained, demoralized, and slowly growing weaker along the blackened ribbon of frontline that stretched from the North Sea to Switzerland. The reporters huddled with Harington were like millions of people across the continent: hoping for a sign, a show, a bit of news—anything that might suggest a shift in the awful fortunes of war.

Had the correspondents understood the violence that was about to unfold—and how it would shape the course of the war—they might have gasped at its scale and ambition. But Harington, a thin, careful man with a neat mustache, apparently offered only a dry hint of what lay ahead.

"Gentlemen, I do not know whether we shall change history tomorrow," he said. "But we shall certainly alter the geography."

Several hours later, starting at 3:10 a.m. on June 7, British engineers detonated 19 enormous mines buried deep below German positions along a ridge outside Messines. The mines were each fired by soldiers and so went off a few seconds apart up and down the length of the ridge, sending geysers of earth, steel, concrete, and bodies spewing into the air and searing the dark sky with orange flame.

The mines, totaling nearly 1 million pounds of explosives, are believed to have created one of the largest human-caused explosions before the nuclear era. On the British side of the front, men were knocked off their feet by the blast. Farther away, in France, the shockwave was mistaken for an earthquake. And the roar of the detonation was reportedly so tremendous that it was even heard by the British Prime Minister in London.

To the Germans, some standing watch in the trenches, some sleeping in underground bunkers, the world itself seemed to split apart. Later estimates suggested that as many as 10,000 soldiers were killed in the explosions, some of them buried alive, many more never seen again.

“For me the most outstanding aspect of the detonation of the Messines mines is that they literally changed the face of the earth,” said Nigel Steel, a senior historian at Imperial War Museums in London and co-author of Passchendaele: The Sacrificial Ground.

“It had a devastating effect on the Germans. With so many mines going off, one after the other, none of them knew how many more there were to come and whether they too were about to be killed by a cataclysmic explosion from deep within the bowels of the earth.”

ORCHESTRATING THE ATTACK

While the mines were a devastating success, they were just the opening act in an attack that had been debated, drafted, and refined for months.

The British Second Army, under the command of General Sir Herbert Plumer, had tried to incorporate hard lessons learned earlier in the war and push past old tactics that had mostly led to bloody stalemate. Plumer’s staff choreographed the moves of nearly all branches of the military, including artillery, air forces, infantry, and engineers, and focused their power along a narrow section of the frontline.

Where earlier battles seemed chaotic, mud-choked, and characterized by the infantry’s slow march toward waiting machine guns, Plumer’s attack was multifaceted, flexible, fast. Within a week, the Battle of Messines was over. The Allies had gained a swath of new ground and, more importantly, gained a rare and inspiring win.

“It is always difficult describing any of the major operations of the First World War as victories,” Steel said. “But I agree that the capture of Messines Ridge was a major success for the British and Imperial armies. It took place at a critical point, counter-acting the disintegrating morale of the French armies and demonstrating that it was possible to conduct a successful attack.”

HEALING FIELDS

One hundred years on, memory of the Battle of Messines has faded. Larger and perhaps more tragic battles, such as The Somme, Passchendale, and Verdun, loom larger in most discussions of the war. The landscape in southwestern Belgium that gave stage to the battle has also softened and healed, at least to the eye. The splintered forests have regrown, the once-flattened villages are restored. Large busses now crawl past the farmhouses and broad green fields, delivering tourists to war memorials and cemeteries. (See "The Hidden World of the Great War.")

There is little obvious evidence that the frontline once passed through this region. There is hardly a note of the tunneling efforts that allowed British sappers, working in secret and in darkness, to place tons of high explosive in deep chambers. And the ridge that once bristled with German fortifications is now a green ripple in otherwise flat, fertile country.

But just below the surface, evidence of this tremendous history is rich and, if you know where and how to look, plentiful.

It’s a powerful lure for archaeologist Martin Brown, one of a handful of European researchers who investigate battlefields of the Great War. Brown has been digging in the Messines off and on for some 20 years.

“To me, it’s the great forgotten battle of the war,” he says. “But Messines deserves remembering. It’s not like the other battles, all mud and catastrophe.”

Several years ago, Brown and some of his colleagues started a non-profit, called The Plugstreet Project, to use archaeology to better understand the soldiers who lived, fought, and died along this sector of the Western Front—specifically in the period surrounding the Battle of Messines. The project’s name is borrowed from wartime British slang for the Belgian village of Ploegsteert, which sits south of Messines and was the site of intense mining operations.

Digging in collapsed trenches and tunnels and on portions of the old battlefield, Brown and colleagues have found bits of uniforms and weapons, sections of trench, and objects that offer more intimate views of the men—such as a small harmonica once carried by a German soldier.

The archaeologists have also encountered unexploded grenades and artillery shells, rusted leftovers that, even after a century spent buried in the damp earth, may still kill. Some of the most unsettling finds, however, point back to the effectiveness and brutal power of the big mines.

ETCHED IN THE EARTH

Mining had been a feature of the war almost since the start, with German, French, and British units burrowing under the no man’s land that separated the front lines. Sometimes the tunnels collapsed and the men inside were buried alive. At other moments, tunnelers suddenly broke through into passageways dug by enemy teams, and hand-to-hand combat followed by lamplight.

While some tunneling operations were large, none approached the scale—or matched the destructive success—of the work at Messines. Not only did it alter the geography, it permanently changed the archaeological record.

“What you have at Messines is material that was lifted up by those huge explosions and then fell back down, burying everything,” Brown says. “You can see an event horizon from 3:10 a.m.—this layer of soil dropped into place by the blast. It’s somewhat like the volcanic eruption at Pompeii, where you have preserved this moment of incredible destruction.”

But unlike the clean casts left by the bodies of victims at Pompeii, Brown and his colleagues found trenches filled with pulverized bone, testament to the shockwaves unleashed by the mines.

“The soldiers were knocked into tiny fragments,” Brown said. “You can read the official reports and hypothesize about this stuff academically, but then, in the field, every now and then there’s something that will bring you up short and you think ‘My God.’”

“TOO SHOCKED TO FIGHT”

On that morning in 1917, just before the mines were fired, some 80,000 Allied soldiers had been moving into position, preparing to attack. After the blast they started forward and soon found themselves shrouded in dust and smoke. Military planners had attempted to calculate the precise time it would take for debris to clear from the air, but they were wrong. For a while a great portion of the British Second Army, comprising Canadian, New Zealand, Australian, and British troops, stumbled forward nearly blind.

Fortunately, resistance was thin, and as first light appeared at the horizon the men began to see why. The earth in all directions was shattered, pitted by craters some 200 feet deep and strewn with smashed trenches and piles of corpses. German survivors rose from the wreckage like ghosts, hands shaking, mouths agape, too shocked to fight.

Among the waves of advancing troops was a private from the 33rd Battalion of the Australian Imperial Force named Alan Mather. He was 37, from Inverell, New South Wales, son of the local mayor. A forensic anthropologist would later describe him as a big man, shaped by hard work, and on that June morning among the things he carried were 150 rounds of ammunition, a pair of grenades, and a rifle with a bayonet fixed beneath its barrel.

Several soldiers later reported that Mather had crossed the German line and was climbing out of a trench when he was killed by shellfire. None of the survivors knew what happened to his body. Like thousands of other Great War soldiers, his remains were never recovered. In official paper work he was described in the hollow three-word phrases: “killed in action,” and “no known grave.” For more than 90 years there was nothing more to say.

Then, in 2008, Brown and his team were digging near the village of Ploegsteert, just north of one of the massive mine craters, when they found a skeleton. It lay face down in the dark earth, the torso smashed by a blast. A backpack was still strapped to the corpse’s shoulders and inside was a German helmet, probably taken as a souvenir, possibly picked up as the soldier crossed the mine-shattered wasteland.

The archaeologists carefully collected the corpse, and soon began searching for its identity. Certain details helped: brass decorations on the uniform, for example, identified the soldier as Australian. Other scientists performed isotope tests to measure oxygen, strontium, and nitrogen levels in the man’s bones. Comparing these levels to geologic maps, the researchers were able to trace his origin back to two possible areas, both in New South Wales.

“From the 33rd Battalion there are some 40 missing men,” Brown said. “For some of them, of course, there will be nothing left. But the isotope test got us down to basically five guys. And from there we did a DNA test.”

The test confirmed Mather’s identity. His relatives were notified, and in 2010 Mather was finally buried with military honors, among comrades, in a cemetery not far from where he fell. This week, Mather’s grand-nieces are traveling to Belgium to visit the grave during centennial commemorations of the battle.

“I was over there myself last week and I went into the cemetery to say hello,” Brown said. “It’s an odd emotional thing that goes beyond what I normally do with my other archeological work. You don’t get this with the Romans, for example. When you deal with burials of that age, you do have this internal dialogue with them. You think, ‘Who are you?’ But you’ll never know in the same way that you do with these battlefield excavations. It’s so much more recent. The story is still going.”