First World War

In 2007, with the spring sun trying to burn through an early morning Belgian mist, it was hard to imagine that this innocuous looking potato field was once the hellish moonscape of the front line.

By the end of the First World War, life on the ground had become untenable. Tons of steel fell from the sky in a near continuous bombardment. The Germans retreated into thick concrete pillboxes. The British dug further and further underground. Today we often picture the British Tommy taking a drag from a cigarette leaning against the wall of his trench. In reality, especially around the Belgian town of Ypres, tens of thousands were living up to thirteen metres beneath the ground.

That's how far they had to dig to be safe from the German shelling.

Memories of Passchendaele

After the Battle of Passchendaele in 1917, when a quarter of a million British and Commonwealth soldiers died as troops advanced the few kilometres to Passchendaele Ridge, a brigade headquarters was built here. Within a week of its completion in 1918, the Germans swept through during their spring offensive and recaptured all the territory gained at such a cost a few months earlier.

They moved into the tunnels and extended them. As the war drew to a close they were finally abandoned as British troops advanced again in the autumn of 1918. The tunnels were eventually sealed and flooded and have remained buried and half forgotten ever since.

Race against time

Peter Barton, historian, author, and expert in underground warfare, was hoping to be able to get back into the tunnels. He pointed out that in those dugouts which he had explored before, everything was preserved, from the actual structure of the thing itself to blankets, to the wire on the bunks, to newspapers.

But it was a race against time. Excavations in a nearby clay-pit meant that the water preserving everything inside the tunnel system may be drained and the process of decay would begin. Worse still, the tunnels may collapse. So for two weeks he and a handful of others took painstaking readings at the surface to try to map out the tunnels, using pegs and tape.

Their work was a mixture of ancient and modern methods. They used ground penetrating radar, which gave them a certain trace. And then they used the ancient method of dowsing, and that matched exactly.

Nasty reminders

Helping him was Johann Van de Wall, a Belgian enthusiast who had successfully excavated smaller tunnels elsewhere. He expressed the feeling that it was hard to believe that people were living there. They must have struggled to live underground, like moles.

A metre or so beneath the surface the diggers revealed a layer of clay which was redder then the rest. The redness was caused by the rust from the artillery and mortar shells, ammunition, helmets, rifles, and bayonets which lay there as a reminder of the horrors of the numerous battles which had been fought here.

Within a few hours of starting work several shells had been unearthed. In Britain this might have meant a call to the Bomb Squad and the evacuation of the local area. But here that would be rather impractical. They were simply being piled up in a corner of the field and from time to time the Belgian authorities would come to take them away to be destroyed.

Secrets could remain

Digging for the tunnels was (and still is) a dangerous and expensive business. They needed to find an entrance to the system, but by 2007 that was yet to happen. The farmer wanted his field back in a few weeks so that he could plant his next crop, which may have meant they that would have to stop digging until the autumn.

It had been deeply frustrating, according to Peter Barton. The depth was the problem; to the roof of one of the tunnels it was a depth of eleven metres, but they also knew that there were entrances, and finding those was proving to be difficult.

Unless they could find a way in, the secrets contained in these tunnels for ninety years would remain there. The fear was that they could be destroyed before they could ever properly be explored.

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