Slovenia lies astride fault lines both geological and cultural. Here, in this compact country bounded by mountain, river and sea, the Eurasian and Adriatic tectonic plates grind against each other, a constant source of tension expressing itself in vaulting ranges and the occasional earthquake. Languages collide also. This is the junction of Slav, Latin and Teuton, the ethnic crossroads of southern central Europe.

Journey through the western half of Slovenia, from the stark, white Julian Alps in the north to sunbathed Istria in the south, and history unfolds through place names. In these borderlands, where war has delivered violent changes of ownership, one name is not enough. In the 20th century, German titles gave way to Italian and then Slovene as borders shifted from west to east and back again.

Take Kobarid, a small town hemmed into a deep mountain valley cut by the racing waters of the River Soca. In summer the sun beats unremittingly on its deserted square, the peace disturbed only by the odd Italian motorcyclist testing his super-tuned machine on the roads curling up through forest towards the surrounding peaks. It is a place to pause, to reflect on a journey half complete, to drink coffee in the afternoon silence.

My wife and two daughters, braver than the supposed man of the family, had taken off into the milky-blue rapids of the Soca for a couple of hours’ daredevil fun. Time at last to do nothing; to sip that coffee.

With only one customer to serve, the woman in the café had time to be curious: from where had we driven? To where were we driving?

“And this place,” I asked, “Anything to see?”

“History. Much history.”

“What history?”

“To the Italians, this is Caporetto. You have heard of Caporetto?”

The town of Piran, on the Adriatic coast

In that moment Kobarid took on a different appearance, dissolving into the monochrome of a century ago: old photographs of ruined buildings pocked by shell fragments and that now-sleepy square crammed with men and horses caught up in the chaos and squalor of sudden, unexpected retreat.

Caporetto was the greatest defeat suffered by Italy during the First World War, a surprise attack by German and Austrian forces in October 1917 that ended in the rout of the defenders. The Italian army, which for more than two years had battered away at the numerically inferior Austrians defending the mountainous western edge of the Habsburg empire, was caught unawares by German troops secretly drafted in from the Western and Eastern fronts, employing sophisticated infiltration tactics.

“So the Soca is…?” I inquired of the woman.

“The Isonzo.”

Of course! The Isonzo is to Italians what the Somme is to the British – a sacrificial waterway written permanently into national history. Eleven significant offensives were launched astride the river by the Italian armies and most of the 600,000 Italians who perished in the Great War met their end in the lands through which it flows. It is still the Isonzo in its lower reaches as it travels through the eastern extremity of Italy towards the Adriatic. But north of the Italian border city of Gorizia (Nova Gorica on the Slovenian side) it is the Soca.

Those inclined to doubt Italian bravery in war should study the Isonzo campaign, which rivalled in suicidal self-sacrifice anything undertaken by Briton, Frenchman or German between 1914 and 1918. The 12th battle was the exception, the only one launched by the Central Powers. Caporetto – Kobarid – owed its military significance to its position near a gap in the western wall of the Isonzo-Soca valley leading out on to the Friulian plain, making it a gateway to Italy.

In the space of a few days the Austro-German army cruelly snatched away ground purchased so dearly by the Italians in the two years since their entry into the war on the Allied side in May 1915. The men from Piedmont, Tuscany and Sicily who had marched so confidently towards their showdown with the supposedly ramshackle Austro-Hungarian Empire, intent on “liberating” supposedly Italian-speaking lands that were in fact inhabited mostly by Slovenes, found themselves being driven back almost to Venice. The Slovene inhabitants of Caporetto-Kobarid came out into the streets to cheer their German “liberators”.

Ernest Hemingway, who served in a field ambulance on the Italian front, was absent from Caporetto but managed to capture its horrors in A Farewell to Arms, describing at one point the random executions carried out by Italian military police desperate to stem the tide of defeat. One who did experience Caporetto at first hand was Erwin Rommel, then serving as a captain in a German mountain regiment. The future Desert Fox earned a Blue Max for the exploits of his company, which bagged thousands of prisoners in outflanking attacks on Italian positions. By the time the armies of Italy stopped running, drawing breath on the banks of the River Piave, they had lost about 300,000 men – 10,000 dead, 30,000 wounded and 260,000 taken prisoner. If the Germans had been able to maintain their momentum, the young Italian republic might have been knocked out of the war.

Stroll through the shaded streets of Kobarid (the Habsburgs knew it as Karfreit) and you come to the museum commemorating those who fell on the peaks and in the ravines. There are plenty of bad military museums dotting the battlefields of Europe, but this is not one of them. Small but expertly conceived, it blends strategic explanation with personal reminiscence. Vicious-looking rusted metal abounds: field guns, rifles, bayonets – and cudgels for the dealing of silent death during nocturnal trench raids. There are faces also, staring out from wall-mounted photographs, naively optimistic, freshly disillusioned or remodelled by flying shrapnel into grotesque and repellent forms.

The dead lie up the hill in a war cemetery, the Italian Charnel House as it is known, a grey, multilayered bastion topped by a spired chapel, shadowed by those endlessly fought-over peaks. The remains of about 7,000 Italian soldiers rest within its ramparts, known and forever unknown.

Like all their countrymen, the Slovenian inhabitants of Kobarid are used to changes of flag. In 1914 this was Austria-Hungary, then Italy, then Yugoslavia and now an independent Slovenia. The Slovenes have existed as a distinct ethnic group for a millennium, but have enjoyed true self-government for only the past 23 years.

Italian troops retreat after defeat at Caporetto in 1917

Geography may have been unkind to this country in regard to neighbours, but it could not have been more generous in terms of landscape. A nation of about two million people, Slovenia is a modern Ruritania, a mini-state, perfectly formed, gratifyingly varied and easy to traverse. One could drive around the entire country in a few days if so inclined, but why do that? One of the great pleasures of touring Slovenia is the lack of urgency its size imparts. It took some time for us to stop worrying about the next leg of our 10-day journey and enjoy dallying in beautiful places, such as the shaded rock pools in the calmer reaches of the Soca. Hotels are always reached in good time for dinner.

Our journey to Kobarid began at Ljubljana’s small airport, two hours’ flying time from Gatwick. First stop was Lake Bohinj, which competes with Lake Bled for the title of Slovenia’s most beautiful inland sea. Bled is the better known of the two, picture-postcard perfect, its castle mounted high on a cliff overlooking the lake and the chapel of the Assumption of Mary on a wooded isle reached by gondola. Tito had a summer home here, as did the rest of the Yugoslav elite. An attempt, partially successful, was made to spoil Bled with the construction of the collection of Communist architectural horrors obligatory at the time. These monstrosities dominate a small stretch of the lakeside in the main town, but are not extensive enough to ruin the fairy tale.

Bled’s disqualification for primacy is its commercialism. It is too pretty, too touristy, too expensive. The gondoliers who ply their trade on the lake enjoy the kind of rip-off fees only a closed shop can provide. Bohinj, quieter, more remote, graced with numerous tiny beaches open to afternoon swimmers and picnickers, is the place to be. Visitors can rent canoes and boats for a Swallows and Amazons afternoon, negotiating the inlets on the far side of the lake, or colonising the wooded islands that dot its surface.

Our journey took us north and west of the great lakes to the ski resort of Kranjska Gora, another borderland, where Slovenian culture rubs up against Austrian, and then south into the great national park of Triglav, named after the highest peak in the Julian Alps. The valleys that nestle in the shadow of the Triglav feed the two great rivers of northern Slovenia, the Sava, a tributary of the Danube, and the Soca. To negotiate the hairpin road from Kranjska Gora to Bovec is to undertake one of Europe’s great drives, a succession of vistas dominated by the great, bleached Julian range. In winter the road is often blocked by snow, but in summer it is a thoroughfare for motorcyclists, testing their brakes. Russian soldiers taken prisoner by the Austrians during the First World War built part of the road and died in their hundreds, swept away by avalanches or landslides. A small Orthodox chapel on a bend remembers them.

The road weaves through Bovec and Kobarid, and then Tolmin, after which the landscape softens into the rolling Tuscan-like country of Goriska Brda, Slovenia’s westernmost wine-growing region. Stay in the fortified, hilltop village of Smartno, in one of the small hotels within its walls, and then venture out to the vineyards for an afternoon’s tasting before settling down in the garden of one of the area’s fine restaurants. For those who cannot afford the price of a Tuscan house this is the place to be: equally beautiful, equally tranquil but cheaper, and only a short drive from the Adriatic.

As the centenary of the outbreak of the First World War approaches, eyes will focus on France and Belgium. But there was another front in Western Europe, not flat but mountainous, specialising in its own horrors. That time is long departed and Slovenia, which saw its last (brief) war only in 1991, when it detached itself from Yugoslavia, looks forward to a century of peace. This Ruritania should do well. To discover its greatest asset, merely pull up by the side of the road in a mountain valley, wind down the window and breathe.

Grapes growing around Smartno

Essentials

Inghams (01483 345791; inghams.co.uk) offers a 14-night, four-centre tour of Slovenia’s highlights, from the mountains in Kranjska Gora to Lake Bohinj and the beautiful coastline of Piran and Portoroz. The Triglav National Park and Coast tour includes four nights in Kranjska Gora at the four-star Hotel Lek, three nights in Lake Bohinj at the four-star Hotel Jezero, four nights in Piran at the four-star Hotel Tartini and three nights in Portoroz at the four-star Hotel Marita, and costs from £949 per person including flights, half-board accommodation and return flight from Gatwick to Ljubljana. Flights are also available at a supplement from Stansted (£19) and Manchester (£59).

The Walk of Peace from the Alps to the Adriatic is a new waymarked trail along the Isonzo Front that takes in military cemeteries, caves, trenches, chapels, monuments and outdoor museums commemorating the Isonzo campaign. For more information see potmiru.si/eng/.

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