If you’re a Hollywood director and you land a big-budget fantasy epic, there’s surely only one place to film it: New Zealand. Ever since Peter Jackson filmed his Lord of the Rings movies there, location scouts have flocked to gaze in awe at the pristine landscapes.

But now Hollywood is moving closer to home. Disney, which shot The Lion, the Witch and the Wardrobe in New Zealand, relocated to Europe for the next film in the series, The Chronicles of Narnia: Prince Caspian. The key battle scenes were shot along the River Soca, in western Slovenia.

Not heard of it? Don’t be too hard on yourself. Although it’s only three hours from London, the Soca (pronounced So-cha) is barely known to British travellers. That’s remiss of us: its valley is one of the most beautiful and unspoilt in all Europe.

Rising in a remote corner of the Julian Alps, the Soca zigs and zags south, hugging and eventually crossing the Italian border before pouring into the Adriatic. What makes it unique is its colour, an iridescent emerald green so vivid, you’d swear there was some hideous chemical plant upstream. There isn’t – just dense forests and limestone cliffs topped with snow-dusted peaks.

The valley has a whiff of Shangri-La about it, the high glacial walls seeming to shield it from the outside world. Nature is exuberant: the grass and wild flowers grow waist high, the butterflies are as big as your fist. The upper reaches of the valley – part of the Triglav National Park – are home to ibex, chamois, golden eagles, marmots and wolves. This is also one of the last known habitats of the Eurasian lynx.

The human population is sparse. Most people work the land, walking their cattle up from the valley floor to the high meadows in summer, and hanging out hay to dry on traditional wooden racks when autumn comes. The villages have unpronounceable names crammed with consonants (try getting your mouth around Gabrje, or Idrsko) and their neat squares are dominated by statues of poets and priests.

Although Slovenia is a small country (inevitably, about the size of Wales), there is no sense of insularity. The people are proud of their independence – they peeled off from Yugoslavia in 1991, relatively peacefully – but also of their more recent membership of the EU. In January this year, they traded in their tolars for euros.

Idyllic though it looks, the Soca Valley has a bloody history. In the first world war, it formed the front line between the Italian army and the combined forces of Austria and Germany. Two years of barbaric fighting in the most inhospitable mountain terrain left 1m soldiers and civilians dead. Ernest Hemingway, who volunteered to serve with the Italians as an ambulance driver, described the futility and chaos of the campaign in A Farewell to Arms.

Today, the Soca is beginning to etch itself onto the tourist map. Just outside the village of Kobarid – scene of a decisive battle that forced the Italians into retreat – a former military hospital has been converted into a gorgeous little hotel, Hisa Franko, which combines stylish modern interiors with a world-class restaurant. In the surrounding hills, a couple of mountain lodges have opened, offering perfect bases for autumn walking breaks.

Many visitors are drawn by the river itself. Fly-fishermen come hoping to snag a rare marble trout, while kayakers test their mettle on some of the most challenging and scenic stretches of white water in Europe. The small town of Bovec has become a watersports mecca, with half a dozen operators offering rafting trips, canyoning and, for the borderline insane, hydrospeeding (you bounce off the rocks, clinging to a polystyrene float). A more sensible option is a half-day rafting trip: you’ll enjoy the raging beauty of the river, and you’ll return home with all your limbs still firmly attached.

Cycling is also popular in the valley. Slovenians like to spend long summer days battling up impossible gradients to high mountain passes (always men, always on their own). If that’s not your thing, you can rent a bike and pedal gently along the valley floor, crisscrossing the river on wobbly wooden footbridges, exchanging waves with villagers and peering into their back gardens (everybody, apparently, has a well-stocked, immaculate vegetable patch).

Hiking is popular with both locals and tourists, and there is a long tradition of public access to private land. There are few fences and no shotgun-toting farmers. According to my guide, Zeljko, it’s considered perfectly all right to wander into another man’s woods and pick his mushrooms.

Pop into a local tourist office and you’ll find piles of maps and guides detailing hundreds of miles of hiking and biking trails. Suggested walks range from gentle hour-long ambles to serious mountain treks that will take several days. (There is a network of huts in the national park where you can stay overnight.)

ONE OF the most beautiful short walks is the hike into Tolmin Gorge. A steep path leads down through sun-dappled woods to the confluence of two ferocious rivers – the Tolminka and the Zadlascica – and up to the Devil’s Bridge, suspended 200ft above the foaming water. Rare flowers, including Slovenian mouse-ear, cling to the sheer walls of the gorge.

Reminders of the war are never far away. Walk through the pastures above the Tolminka and you’ll eventually come to a small wooden church, built by Austrian soldiers in 1916. The interior is painted blue, black and gold, with swirling art-nouveau murals and folding panels carved with the names of 2,800 dead soldiers.

In Kobarid, an award-winning museum tells the story of the Soca front; in the surrounding hills, some of the battlements have been restored to create open-air museums. The most impressive is at Kolovrat, on a ridge that marks the border between Slovenia and Italy. The Italians spent 2½ years constructing a network of tunnels, trenches and bunkers, many beautifully engineered with paved stone floors and chiselled staircases. All the work was for naught: the entire ridge was overrun in a single night by German forces under the command of an ambitious young officer called Erwin Rommel.

Today, the unrestored trenches are collapsing back into the soil, covered with cherry blossom and lilies of the valley. Below the ridge, a new road is being built through the forest, connecting Italy and Slovenia. It will open next year, coinciding with the removal of the border posts between the two countries.

Down on the valley floor, it is easy to imagine you are in some long-forgotten, unspoilt corner of Italy. At a pavement cafe in Tolmin, I lunched on prosciutto, bread soaked in olive oil and mushroom risotto. Only the prices were unfamiliar: a two-course lunch for less than a fiver.

The village of Kobarid is tiny, but it manages to support two outstanding restaurants. On the main drag, Topli Val is regularly full of Italians, who hop over the border for octopus carpaccio and fresh langoustines. Unlikely though it sounds, the dessert of summer fruits with potato gnocchi is outrageously good.

The second, Hisa Franko, offers the kind of full-on foodie experience you would normally expect chez Heston or Gordon. Its eight-course tasting menu changes seasonally and features beautifully executed dishes such as potato ravioli, venison with chocolate, sea bass fillet (steamed at a fashionable 57C) and ricotta ice cream. At £35, it’s absurdly good value. Mind you, that’s something you could say for the whole area – and it’s a whole lot easier to get to than New Zealand.

— Mark Hodson was a guest of Just Slovenia

Travel brief

Getting there: the nearest airport is Trieste, about 90 minutes away by road in Italy. Ryanair (0871 246 0000, www.ryanair.com) flies there from Stansted. Alternatively, Ljubljana is a two-hour drive away: fly there with EasyJet (www.easyjet.com) or Adria Airways (020 7734 4630, www.adria-airways.com). A car is essential: Travelsupermarket (www.travelsupermarket.co.uk) has three days’ inclusive hire from Trieste or Ljubljana from £60. Or try Holiday Autos (0870 400 4461, www.holidayautos.co.uk).

Where to stay: Hisa Franko (00 386 5 389 4120, www.hisafranko.com) has doubles from £68, B&B. The Topli Val restaurant is part of the Hotel Hvala (00 386 5 389 9300, www.hotel-hvala.si), which has comfortable doubles from £67, B&B. Overlooking the confluence of the Soca and Lepenca rivers, Pristava Lepena (00 386 5 388 9900, www.pristava-lepena.com; doubles from £64, B&B), has 13 cosy wooden cottages on a remote alpine meadow. The charming owners keep three pure-bred Lipizzaner horses for guests to ride; there’s also a tennis court, a pool and a weekly spit roast. Even more remote, Nebesa (00 386 5 384 4620, www.nebesa.si) – the name means heaven – on a hillside 2,000ft above the valley floor, has four stylish contemporary cottages (sleeping two), an indoor pool and a sauna. Prices start at £141 per night, self-catering. For accommodation inside the national park, including mountain huts, contact the park office (00 386 4 578 0226, www.tnp.si).

Tour operators: Just Slovenia (01373 814230, www.justslovenia.co.uk) can tailor-make holidays to the Soca Valley. Three nights, B&B, at Hisa Franko start at £323 in October, including flights and car hire. Or try Holiday Options (0844 477 0451, www.holidayoptions.co.uk).

Activities: for fishing permits, contact the Angling Club of Tolmin (00 386 5 381 1710, www.flyfishing.si) or buy one at the Hvala. For details of Kobarid Museum and the open-air museums, visit www.kobariski-muzej.si and www.potimiruvposocju.si. Mountain bikes can be rented in Bovec or Tolmin for £12 per day. Rafting and canyoning trips are widely available for about £20. Walking and cycling maps are available from local tourist offices.

Further information: Slovenian Tourist Board (0870 225 5305, www.slovenia.info).

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