Close to the top of Mount Maglić, on the Bosnia-Montenegro border, a deafening clap of thunder rips across rugged Piva national park. The summit of the 2,386-metre limestone peak is not far away, but with a glance at the darkening sky, our guide Lorenc decides it’s best to turn back.

We weave our way down towards perfectly heart-shaped Lake Trnovačko, just reaching a forest as the downpour hits. When the storm passes, the view across the valley is our reward – glittering, luminous and streaked with post-squall mist. The slopes are lined with tufted grass and a golden eagle floats overhead. The scene silences us, and we walk in quiet contemplation until Lorenc stops us to point out a sign: “Welcome to Bosnia”.

There’s no checkpoint and no fuss – perhaps surprising, given the history of these once war-torn Balkan countries. We’re hiking part of a new mega-trail – the Via Dinarica – and up here, the conflicts across the former Yugoslavia feel firmly in the past. The main artery is the White trail, from Slovenia to Albania – via Croatia, Bosnia & Herzegovina and Montengro, and soon to be extended into Kosovo – following the Dinaric Alps for 1,260km, taking in the highest peaks. Opened fully in 2017, it has mapped and united old trails, shepherd paths, royal hunting grounds and military routes, with accommodation in mountain huts, riverside cabins and lodges along the way.

When two further trails have been completed (blue, along the coastline, and green, connecting small villages – see the map above), the route will also take in Serbia, uniting seven Balkans countries.

Facebook Twitter Pinterest Looking out on the Durmitor massif in Montenegro. Photograph: Leo Plunkett

It takes about three months to hike the White trail from end to end, but with just seven days to spare I’ve joined a tour with Green Visions, a Bosnian operator involved in the route’s development, focusing on a stretch across three spectacular contiguous national parks: Sutjeska in eastern Bosnia, Piva on the border, and Durmitor in north-western Montenegro. We hike for an average of six hours a day, covering 64km in six days, with a day off for rafting and some road transfers to save time.

Our group of 10 meet in Sarajevo, Bosnia’s capital, about three hours north-west of the trail, and we head to Hotel Mladost, a lodge with dorms at the edge of Sutjeska, our base for two nights. It’s late summer, and the next morning dawns bright and clear as we set off to explore the park, site of the eponymous second world war battle. On the way we pass Donje Bare – one of many glacial lakes that dot the mountains – and a concrete monument to Yugoslav soldiers who died in the war.

Facebook Twitter Pinterest On the trail in Piva national park. Photograph: Leo Plunkett

As we begin a two-hour ascent of the 1,858-metre Ugljesin, Lorenc points out soft circular indents in the hillside – craters from aerial raids. Today they are carpeted with flowers: fading narcissi, purple crocuses, fragrant thyme, mint and oregano. It’s a landscape that’s easy to love: a collage of rolling hills, craggy peaks, squat evergreens and fields of flowers that turn gold in the late-afternoon sun.

“Even though all this is in our backyard, hiking is not yet second-nature to people in the Balkans,” says Lorenc, a former Yugoslav boy scout. The Via Dinarica, he says, is as much for locals as for tourists and will, he hopes, encourage people to explore their homeland.

Meals at Camp Highlander ‘are a feast’

We descend at sunset for a meal of roast meats, ripe tomatoes and giant wedges of fried cheese at the hotel. Sleep comes easily, and the next day more hiking awaits in Piva national park and the Perućica reserve – one of the last remaining primeval forests in Europe, thick with 300-year-old Greek maples, firs, spruce and beech. Wherever we go we rarely pass another soul.

On the third day, we swap land for water, paddling down the electric-blue Tara river through the deepest canyon in Europe. We raft for three hours between limestone walls streaked with mauve manganese, disembarking on the steps of the riverside Camp Highlander, where we sleep in tiny log cabins. Meals here are a feast, with spiral filo pastries filled with meat, cheese or spinach (burek or pita), pillowy breads with kajmak (clotted cream) and ajvar (a red pepper paste), cured meat and cheese, fresh figs, tomatoes and grapes, and whole-roasted lamb.

Leaving Bosnia behind, our route takes us deeper into Montenegro, where we trek from the Mratinje dam across a grassy plateau for seven hours to the edge of Durmitor national park, passing mysterious, cross-shaped medieval tombstones. Filmy with sweat, we arrive on the doorstep of Dragan, a Montenegran shepherd who runs Sokolina Guesthouse, a small white dwelling on the edge of the canyon, overlooking the 96,000-acre park. He refurbished the unused family home 10 years ago after learning that it was on the route of a new cross-border trail.

“My friends and family thought I was crazy – they said no one would come to such a remote place,” he tells us. But now he gets visitors from as far afield as the Philippines and Australia.

Facebook Twitter Pinterest Camp Highlander, on the Tara river in Bosnia, offers rafting, and great food.

As the sunset turns the sky violet, we drink homemade pear rakija (brandy), passed around in a single glass. The next morning, Dragan fries up savoury doughnuts served with sour cream, washed down with wild oregano tea and strong Bosnian coffee brewed over an open flame. We continue into the park, our backpacks carrying sleeping bags and food supplies for the final days when we’ll stay in rustic mountain huts.

Over two long days we cover 30km, hiking through humid deciduous forest, the imposing Durmitor massif our backdrop. We swim in freezing, blue-green Škrka lake, surrounded by pristine spruce forest and karst cliffs. A herd of long-lashed brown cows join us at our lakeside hut that evening, and a chamois, the region’s elegant endemic goat-antelope, trots down to the water. There’s no electricity so we light candles, cook pasta over a fire and share a bottle of wine before rolling out our sleeping bags.

Six days on the trail pass too quickly, and before I’m ready to leave we’re back in Sarajevo. I can’t resist squeezing in one last hike on a segment of the trail near the city before I go: a seven-hour, circular trek to Lukomir, the highest and most remote inhabited village in Bosnia. At that windy, tin-roofed settlement, above a karst canyon, I stop for one last spinach pie.

I recall something Lorenc said one night on the trail: “Hiking in the Balkans still sounds exotic to many people. It’s beautiful here, of course, but I hope one day it will be an unsurprising thing to do.”

Looking at this remarkable landscape, I think he will be proved right. But, in the meantime, I relish the quiet.

• The trip was provided by Green Visions, whose one-week Via Dinarica tour through Bosnia and Montenegro costs €835, including guides, most meals, transfers and lodging. It also runs day hikes to places such as Lukomir village (€45). Austrian Airlines flies from Heathrow to Sarajevo from £300 return. See viadinarica.com for trail maps, mountain huts and other accommodation. The main hiking season runs from May to September. Snowshoeing and other activities are possible in winter

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