Is camping the best kind of family holiday? I know plenty of parents who think so. It’s something to do not just with the immersion in nature and fresh air but the sheer amount of day-to-day activity involved, from the mundane (water fetching, sleeping bag stashing) to the thrilling (fire stoking, s’mores toasting). Restless kids are rarely bored.

But camping with your own gear limits your horizons. You need a car to lug your stuff, which means you can only go so far afield. It’s no surprise, then, that campervan-hire companies are proliferating in popular European destinations and bookings from families in peak season are on the rise. A campervan trip is, of course, much more expensive than camping (van hire is roughly the same per day as a mid-range hotel or self-catering option), but comes in slightly cheaper than a fly-drive holiday as you save the car hire. It’s also a good sustainable option: taking the train to your campervan destination is greener than flying, and more climate-friendly than driving a diesel van long distances from home.

To get off the beaten track my husband and I and our two boys (aged six and nine) choose north-east Portugal, away from the crush of the Med and the busy Algarve. We book a freshly converted VW T6 Transporter from Siesta Campers, run by Brits Loyd and Claire, who started refurbishing vintage VWs in the 90s and who lease vans (classic and new) from all over Portugal, including Lisbon, Faro, Porto and even Madeira.

The great outdoors: preparing for another day by the water. Photograph: Siesta Campers

After a weekend exploring Porto, we’re met on a back street by a charming Siesta rep who hands over the van keys and runs through a slightly overwhelmingly list of instructions. After marvelling over the ingenious details, from the way a mere tug on a strap sends the back seats sliding away to form a double bed, to the dinky shower tucked into a cupboard and the solar-powered fridge and USB points, we are, somewhat gingerly, on the road.

Away from the blustery coast, the two major destinations for wilderness-seekers are the port-producing Douro valley and the Minho region’s rugged Peneda-Gerês national park, which covers the mountain ridges in Portugal’s north-eastern corner. Just outside the park – and only 100km from Porto – our first stop is Lima Escape, on a hillside over a wide bend in the river Lima. The campsite is not small (there are 400 pitches and a smattering of glamping cabins), but it’s peaceful – even in August – and the best van pitches under the pine canopy have terrific views, not least of novice paddleboarders, drifting stiffly past like anxious ducks.

Peneda-Gerês is a wild swimming paradise. In the mornings, we swim from the small beach of mud-coloured sand at the foot of the campsite. We take short treks into the surrounding oak-and-pine forests to nearby fern-fringed “lacs” – small, clear spring water pools – where the water is breath-catchingly cold. We hire kayaks and pootle around on the river. The kids are in heaven – partly because they are very well-slept. There’s little to do on a campsite after the sun has gone down – and there’s something very alluring about going to sleep in the pop-up roof of a van, with the stars visible through the net windows.

Inside story … the vans have a dinky shower, a solar-powered fridge and USB points

The menu at the campsite restaurant is intimidatingly rustic, but that’s a line you tread, we come to learn, when eating out in rural Portugal. Meals we fail to finish included a grilled octopus tentacle the size of a human arm and a burger as pink as the slice of ham perching on its top (the term “hamburger” is taken very literally here). Anyway, eating chez nous at the picnic table, having grilled sausages on one of the campsite’s purpose-built barbecues, is the best way to dine.

One drawback of sleeping in your transport is having to pack up for a day out, but the region’s humble charms are worth the effort. The Peneda-Gerês hillsides, dotted with sleepy granite villages, host a number of waterfalls and many more of those icy spring-water pools (more than one person boasts to us that the region has the cleanest rivers and streams in Portugal). We spend an afternoon near the village of Ermida, recovering from the nerve-fraying experience of negotiating endless hairpin bends by lazing on sun-toasted rocks and listening to locals screeching as they plunge into the waterfalls.

Another excursion takes us west to Arcos de Valdevez, where we park opposite the town beach (Praia Fluvial da Valeta) and take a recently built “eco-walk” which winds, via wooden bridges and walkways, along the bank of the River Vez, north and out of town. After 90 hot and sweaty minutes (we mistime our walk for midday – typical English), the path passes under a small road bridge and on to the terrace of Bar do Rio, a chic-cum-chaotic bar-cum-restaurant on a shallow turn of the river where the kids swim while we drink cold beers (just ₤1!) before catching an Uber back to the van.

Messing about on the river … kayaking at Peneda-Gerês, also a wild swimming paradise. Photograph: Sarah Donaldson

We spend the final days of our trip at Vila Praia de Âncora, a windswept coastal town just south of the Spanish border. Do Paco, our slightly scruffy campsite 15 minutes’ walk from the beach, lacks the dramatic scenery of Lima, but has a laidback charm, and access to a couple of small river beaches. The coastline itself is stunning, but only the hardiest swimmers – and a handful of brazen kite surfers – brave the cliff-like waves. At Fortaleza, a bustling seafront restaurant lined with lobster tanks, we have some of the best steak of our lives, cooked slice by slice on a hot stone at the table.

Would we campervan again? There were challenges. Cooking breakfast, hungover and crouching over the van’s gas rings, tested my husband’s patience. The constant rearranging meant we were forever misplacing stuff. I don’t think my family will ever be the dig-your-own-toilet, forage-for-firewood wild-camping type, but no hotel can beat the sense of freedom of knowing you can just pack up and head somewhere new. Or the delicious contentment of brewing coffee as the morning sun creeps through the sweet-smelling pines. I even found myself Googling “second-hand campervans” when we got home…

Way to go

Siesta Campers’ basic fee for a compact, modern van for four is around €160 a day (peak season) including bedding, kitchen equipment, AC, gas bottle and motorway toll charger (€15 activation fee). For an extra charge, you can hire a pop-up tent. An extra €150 buys one-way hire, where you pick up and drop off in different cities

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