At first glance Peio is a small alpine ski resort like many others in northern Italy. In winter it is popular with middle-class Italians as well as, increasingly, Russian tourists. In summer there’s good hiking in the Stelvio National Park. It has a spa, shops that sell a dozen different kinds of grappa, and, perhaps, aspirations to be the next Cortina. A cable car was inaugurated three years ago, and a multi-storey car park is under construction.

But in Peio, reminders of the region’s past are never far away. Stroll up through the village and, passing the tiny First World War museum on your left, you come to the 15th-century San Rocco church with its Austro-Hungarian cemetery and sign requesting massimo rispetto. Here, one sunny day last September, 500 people attended the funeral of two soldiers who fell in battle in May 1918.

In Peio, you feel, the First World War never quite ended. And in one very real sense, it lives on, thanks to the preserving properties of ice. For Peio was once the highest village in the Austro-Hungarian empire, and had a ringside seat to a little-known but spectacular episode of that conflict called the White War.

In 1914 both Trentino – the province in which Peio lies – and the neighbouring South Tyrol were Hapsburg domains. Italy, recently unified and eager to settle her frontiers permanently, looked on the two provinces, along with Trieste, as ‘unredeemed lands’. In May 1915, with the aim of reclaiming them, she entered the war on the side of the Allies. Conflict was already raging on the western and eastern fronts; now a third front opened up. It stretched from the Julian Alps, which Italy now shares with Slovenia in the east, to the Ortler massif near the Swiss border further west – some 250 miles.

As much of the front was at altitudes of over 6,500ft, a new kind of war had to be developed. The Italians already had specialist mountain troops – the Alpini with their famous feathered caps – but the Austrians had to create the equivalent: the Kaiserschützen. They were supported by artillery and engineers who constructed an entire infrastructure of war at altitude, including trenches carved out of the ice and rudimentary cableways for transporting men and munitions to the peaks.

In the decades that followed the armistice, the world warmed up and the glaciers began to retreat, revealing the debris of the White War. The material that, beginning in the 1990s, began to flood out of the mountains was remarkably well preserved. It included a love letter, addressed to Maria and never sent, and an ode to a louse, ‘friend of my long days’, scribbled on a page of an Austrian soldier’s diary.

The front line between the Allied forces and those of the Central Powers as seen from Punta Linke, 1918. Photo: Museo della Grande Guerra, Peio

The bodies, when they came, were often mummified. The two soldiers interred last September were blond, blue-eyed Austrians aged 17 and 18 years old, who died on the Presena glacier and were buried by their comrades, top-to-toe, in a crevasse. Both had bulletholes in their skulls. One still had a spoon tucked into his puttees — common practice among soldiers who travelled from trench to trench and ate out of communal pots. When Franco Nicolis of the Archaeological Heritage Office in the provincial capital, Trento, saw them, he says, his first thought was for their mothers. ‘They feel contemporary. They come out of the ice just as they went in,’ he says. In all likelihood the soldiers’ mothers never discovered their sons’ fate.

One of the oddities of the White War was that both the Alpini and the Kaiserschützen recruited local men who knew the mountains, which meant that they often knew each other too. Sometimes family loyalties were split. ‘There are many stories of people hearing the voice of a brother or a cousin in the thick of battle,’ Nicolis says.

For both sides the worst enemy was the weather, which killed more men than the fighting. At those altitudes, the temperature could fall to -30C, and the ‘white death’ — death by avalanche — claimed thousands of lives.

The remains of two Austrian soldiers found on the Presena Glacier in 2012. Photo: Office for Archaeological Finds, Autonomous Province of Trento

The people of Peio lived these stories because unlike the inhabitants of other frontline villages, they stayed put. ‘The Emperor decreed that this village should not be evacuated,’ Angelo Dalpez, Peio’s mayor, says. ‘As the highest village in the empire, it was symbolic — a message to the rest.’ They worked as porters and suppliers of food. They tended the injured, buried the dead, and witnessed the remodelling of their ancestral landscape (shelling lowered the summit of one mountain, San Matteo, by 20ft).

In 1919 the Treaty of Saint-Germain-en-Laye awarded Trentino to Italy. ‘There was never any clash,’ Nicolis says. ‘No revolution. It was an entirely smooth transition.’ People here had always felt autonomous, in their mountainous border region, and under the new arrangement the Italian government granted them a degree of autonomy. They carried on drinking grappa, eating knödel and speaking Italian (which had been one of the 12 official languages of the empire), but they never forgot their history. Many of their relations had fought on the Hapsburg side, and when the soldiers started melting out of the ice, they looked on them as their grand-fathers or great-grandfathers.

This became clear in 2004, when Maurizio Vicenzi, a local mountain guide and the director of Peio’s war museum, whose own family fought for the Austrians, stumbled on the mummified remains of three Hapsburg soldiers hanging upside down out of an ice wall near San Matteo — at 12,000ft, scene of some of the highest battles in history. The three were unarmed and had bandages in their pockets, suggesting they may have been stretcher-bearers who died in the last battle for the mountain, on September 3 1918. When a pathologist was granted permission to study one of the bodies, to try to understand the mummification process, there was an outcry among local people who felt that the dead were being profaned.

The mummified remains of three Hapsburg soldiers found in 2004. Photo: Museo della Grande Guerra, Peio

The three now lie in the cemetery at San Rocco next to the two from the Presena glacier, in five unmarked graves. All have passed through the lab of the forensic anthropologist Daniel Gaudio and his team, in Vicenza. His priority is to name the mummified soldiers if he can. It is rare that he succeeds for although he can almost always extract DNA, contextual information about the circumstances of their deaths tends to be lacking, meaning that he can’t locate potential living relations to find a match.

In 2005 Vicenzi started exploring a site called Punta Linke, almost 6,500ft above Peio. He found a natural cave in the ice and material scattered over the surface — steel helmets, straw overshoes, boxes of ammunition — and realised there was a structure beneath. With friends from Peio, Great War enthusiasts all, he investigated. Nicolis’s team arrived on the scene two summers later, and together they excavated a wooden cabin — a station on one of the cableways that provided vital supplies to the troops.

The cabin is built against the rocky peak of Punta Linke, and behind it a tunnel runs for 100ft through that peak. When the team first found the tunnel, which is the height of a man, it was filled with ice that they cleared with the help of giant fans. During the war wooden crates brought up on the cableway were pushed through the tunnel before being launched on the final stage of their journey – an impressive 4,000ft leap – using an unsupported cableway, across the glacier to the front line. Beside the tunnel’s exit is a window through which a lookout watched the crates go.

The tunnel dug by Austrian soldiers behind the cableway station at Punta Linke. Photo: Laura Spinney

Inside the cabin is a Sendling engine, made in Munich, dismantled by the departing Austrians and now restored. The archaeologists have left in place three documents they found pinned to the wall: handwritten instructions for operating the engine, a page from an illustrated newspaper, Wiener Bilder, showing Viennese people queuing to buy food, which by 1916 was in short supply in the crumbling empire, and a postcard addressed to a surgeon in the engineering corps, Georg Kristof, from his wife in Bohemia. The card shows a woman sleeping peacefully and is signed, in Czech, ‘Your abandoned lover’.

In their lab in Trento, Nicolis and his colleague Nicola Cappellozza show me the love letter written to Maria, which was found in a box of letters ready to be posted, on Punta Cadini (11,500ft), and dated late in 1918. (The archaeologists do not want to reveal the contents of the letter until they can trace Maria’s family.) ‘Perhaps hostilities ended before they could be sent,’ Nicolis says. Other finds include fragments of newspaper printed in Cyrillic. The Russian tourists who visit Peio today may not know it, but other Russians were there before them — prisoners brought from the eastern front and used as pack mules, or put to work weaving the straw overshoes that protected the Austrians’ feet from frostbite.

Documents pinned to the wall by soldiers at the Punta Linke cableway station. Photo: Laura Spinney

Peio’s war museum fills out the picture. Inside its display cases are primitive-looking surgical instruments of the kind Kristof might have used, rosaries, porcelain pipes that resemble small saxophones, decorated in the Tyrolian style, and ‘trench art’ carved out of fragments of shells or shell casings. In the hungry period following the armistice, the villagers roamed the mountains looking to salvage material they could reuse or sell. Some pieces they kept as souvenirs, donating them to the museum when it opened 10 years ago. ‘They consider the museum their collective property,’ Dalpez says. ‘They’re proud of it.’

More than 80 soldiers who fell in the White War have come to light in recent decades. There are certainly more to come, but one body continues to elude the rescuers – that of Arnaldo Berni, the 24-year-old captain who led the Italians to their conquest of San Matteo on August 13 1918. Berni’s story illustrates the tragedy of a war where, as the British historian Mark Thompson explained in his 2008 book, The White War, Herculean feats produced trivial territorial gains, and no one down below took much notice.

An Austrian rifle found melting out of the ice. Photo: Museo della Grande Guerra, Peio

After his victory, in a letter that must have slipped past the censors, Berni complained to relations about the press coverage. ‘There is a short and confused description of our battle, which was in fact brilliant and incurred very little loss of life… The journalists don’t come to us at such high altitudes, so the prodigious efforts of our men are not known.’ He died three weeks later, when the Austrians — on their way to recapturing San Matteo — dropped a shell on the crevasse in which he was sheltering. Two months later, the Italians dealt a shattering blow to the Austro-Hungarian war effort at Vittorio Veneto, on the Venetian plain, and the war was over.

There have been many attempts to find Berni over the years, first by his own men, then by his devoted half-sister, Margherita — the once skinny little girl he nicknamed Ossicino, or ‘Little Bone’ — who for long after the war made annual pilgrimages to the mountains, and finally by Vicenzi, Cappellozza and others, who in 2009 climbed down into the crevasse where the hero almost certainly met his death. They found no trace of him, but Cappellozza hasn’t forgotten the experience. ‘We were able to walk horizontally a long way. I remember the colours in the ice — the blues, the violets.’

Inside the Peio's war museum. Photo: Laura Spinney

In the summer of 2013, just before the snow came, Nicolis’s team put the finishing touches to the restoration of the way-station at Punta Linke. From next summer, intrepid hikers will be able to visit this simple monument and, as he puts it, ‘smell the war’. Sometimes, Nicolis says, he looks through the window at Punta Linke and tries to see the mountains as the soldiers did. Those, like Kristof, who came from distant corners of the empire, must have been mystified by the struggle for this inhospitable wilderness. For others, local highlanders, the mountains were the prize and the Emperor the abstraction, but one for whom they were expected to fight men they had climbed with all their lives.

In both cases, he believes, the mountains signified death before they signified beauty. ‘Snow is truly a sign of mourning,’ Giuseppe Ungaretti, the Italian war poet, wrote in 1917. Peio’s mayor has a different take on things. At the funeral of the Presena pair, three anthems were played — the Italian, the Austrian and the Ode to Joy. ‘The people who fought here,’ he says, ‘were Europeans before their time.’

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