Motoring down the Croatian coast towards the city of Zadar, the road sweeps majestically south. To the right are necklaces of islands in a dazzling turquoise sea and sudden sweet coves with antique shuttered houses, their front porches shaded by vines, a fishing boat at the front door. This is the Croatia most visitors come to see. On the other side are mountains capped in threatening cloud. That is the Croatia most people do not bother with, the one I have been persuaded to try.

In the little town of Starigrad we abandon the sea and take a narrow lane towards the mountains. I’ve come with a friend who visited the area as a teenager and has never forgotten the adventure. Behind the narrow entrance to the Velika Paklenica gorge, he assures me, is a magical world that few people see. I’m hoping he is right.

The town of Starigrad beneath the mountains Photograph: Alamy

We make base camp in a cottage near the gorge mouth (from €80 a night, sleeps 4) and next morning set out into Paklenica national park. The lane leads us into the jaws of the first spectacular 14km-long canyon. Crowds of climbers are already tackling the crags but we press on to where the canyon opens out a little and the rock walls become stupendously high. On the right is Anića Kuk, one of the most famous climbing sites in the world, its north-west face a 400-metre wall of limestone, Europe’s answer to Yosemite’s El Capitan. Over a late picnic lunch we watch the climbers on it. The park is 95 sq km embedded in a far more extensive mountain wilderness.

We hike onwards, always by the tumbling river and in the shade of forest. A smooth snake whips across in front of us, its body as thick as my wrist. There are emerald green lizards too, blinking at us from the bushes. Eventually, as the sun is about to set, we reach our goal: Paklenica mountain hut, a neat wooden chalet with deep gables over red shutters and a balcony. There is one silent old man in sunglasses, sitting impassively at a table with a chequered cloth. And nearby, paintbrush in hand, is the caretaker, Dalibor, the polar opposite: irrepressibly loud and cheerful.

The Paklenica mountain hut Photograph: Kevin Rushby

“That’s Vuke, the Wolf,” he says, introducing his elderly friend. “He knows every inch of this national park. There’s only him, me and my girlfriend, Korana, living here. We are the gatekeepers to the upper world.”

I live on the edge of civilisation. People ask for hot showers and I point them to the river Dalibor Bračić

We are just digesting this pronouncement when a pair of young hikers arrive. Has Dalibor got a wifi code and a place to charge phones?

“My friends,” he tells them, “you come here to charge your own batteries, not those in your phone. And there is no wifi. You have left all that behind you.”

The pair look around uneasily. Does he sell bottled water?

“Mountain water is free.” He points to the pipe that comes from a spring. Dalibor, I quickly realise, is no ordinary caretaker. He serves us shots of local liquor and tells us his family story: “In the days of emperor Franz Josef my grandmother used to smuggle salt through these mountains.”

Dalibor Bračić, custodian of the Paklenica hut, right, and his friend, Vuke, also known as the Wolf. Photograph: Kevin Rushby

He himself was born on the coast, in Zadar, where he became a DJ. Then in 1991 the war came, a conflict that has left deep psychological scars in this area. For Dalibor, the only redeeming thing was that it led him back to the family origins: the mountains.

As we climb, the orchids and oaks give way to primroses and beech which then defer to bellflowers and pines

“I live on the edge of civilisation,” he says. “People ask for hot showers and I point them to the river. A lot of people turn back when they find there’s no bottled water or ice-cream. This place is a filter for what lies beyond.”

We keep our phones hidden. Can he help us? We spread the map. “Spend the night here,” he advises. “Tomorrow, take this path …” His finger describes a long arc. “Up here at Struge there is a refuge hut. Take food, sleeping bags, compass and down jackets. From there you reach the summit of the Velebit mountains, then come down here – there’s another refuge hut. We’ve got 11 across the park. First come, first served, all free.”

That night we eat wild boar stew, washed down with rough red wine – homemade and very affordable – and get a brief botanical lesson from Korana. The park has 79 endemic species and is regarded as a world-class location for wild flowers.

Paklenica national park. Photograph: Alamy

We start next day along a fine footpath through the forest. There are wolves and lynx up here but all we spot is a hare. Forty years ago there was a substantial human presence but the last shepherd retired to Zadar in 2016 at the age of 94. Without the sheep, the forest has rebounded and along with it, bears. Dalibor spotted a mother and cubs on the track only a couple of weeks before. The resurgent forest suits them, a forest that is now the largest in Dalmatia.

As we climb, the orchids and oaks give way to primroses and beech which then defer to bellflowers and pines, the latter rapidly dwindling in size. We emerge on a high pass that is spangled with gentians of perfect blue. Further along, golden crocuses are forcing their way through patches of snow and we find the refuge, a gnarled cabin with a wood fire for cooking and bunk beds hewn from logs.

At the height of summer I imagine you would want to arrive early to guarantee a bed, or carry a tent, but not in spring – the place is empty. All the various refuges were built by the 600 members of the Paklenica Mountain Association and they have done a sterling job: not too much comfort, but plenty of homespun charm. Water is in the well half a mile away through a dwarf birch forest. “It never dries up – even in high summer,” Dalibor had told us. We eat hunks of local air-dried ham tenderised with slivowitz, a fruit brandy. The water is like chilled nectar.

Gentians on a high pass in the mountains. Photograph: Kevin Rushby

At dawn we meander off through the dwarf forest and by the well find a sign pointing south, up the slope towards the summit of the range, Mount Vaganski (1,757 metres). The map shows some ominous pink blotches nearby: minefields. During the Balkan wars of independence in 1991-95, Serbian forces pushed up to this ridge, hoping to establish a permanent grip on Croatian territory. By the time they were defeated, some 20,000 people had died and the Croatian economy was in ruins. For the Mountain Association the challenge has been to rebuild footpaths away from those danger areas, much of the pioneering trail work being done by Dalibor’s inscrutable companion, the Wolf. There are now around 150km of trails.

Heading for the summit we enter a whirlwind of cloud and mist. In the hollows are deep drifts of snow, on the ridges a knee-high forest of stunted twisted pines. Everything is dripping with icy water. The summit is marked by a cross and a tin box containing a visitors’ book. No one, we note, has signed it for some time.

Heading for the summit of Mount Vaganski. Photograph: Kevin Rushby

The descent is tricky: long steep snow glides that later become vast scree slopes. Ours is a rapid weekend visit but we both feel like we have spent weeks in the wilderness. By the end of the afternoon we are back at the main hut.

The Wolf is still sitting, immobile and silent, by the door. A group of hikers is leaving after a night in Dalibor’s cabin. I ask Dalibor what the Wolf makes of the visitors? “He says they need to stop looking at their phones and learn to sit for a whole day doing nothing. That is the forgotten art of the shepherd.”

We eat more superb home cooking. Does the hut ever get full? “We have 50 proper beds, but one time we coped with 250.”

We are fortunate to have it almost to ourselves. In the dining room Dalibor reveals a television set. We are shocked. “You have electricity? For emergencies?”

He laughs. “Yes, absolutely: I think there’s a Champions League match on tonight.”

Way to go

The trip was provided by Croatia Tourism. Malik Adventures does a six-day adventure tour that includes a hike in the Velebit mountains and two nights at the hut for €850pp. A bed at Paklenica mountain hut is £11pp.

Getting there

Ryanair flies from Stansted and Manchester to Zadar or Rijeka.

When to go

Spring is best for wild flowers. Average highs of 26C in the national park in July.

Looking for walking holiday inspiration? Browse The Guardian’s selection of walking holidays on the Guardian Holidays website