The back of beyond used to be easy to find. It was a village called Imlil, a 90-minute drive out of Marrakesh. From there, you trekked up Jebel Toubkal, North Africa’s highest mountain, to see something of the great unknown. Sleeping options were simple, too: either bring your own sleeping bag or throw down Berber blankets.

Cheap flights and Marrakesh’s racing popularity have changed things. Villages that could not be reached by road in the 1990s are now accessible by car and studded with television antennae. Richard Branson owns a kasbah in the shadow of the mountain. Toubkal has become the great known.

So, where to go without fear of bumping into your neighbour? People told me I should look up a mountain called M’Goun.

At 13,356ft, just 309ft short of Jebel Toubkal, M’Goun still feels remote. It’s not much more than 100 miles from Marrakesh, but it can take the best part of a day to get there – especially if, like us, you linger over breakfast in your riad and stop for lunch at the Cascades d’Ouzoud, memorable for the daring of the Barbary apes and the beauty of the waterfalls.

By the time we wound up towards the M’Goun peak, late sun was bronzing the foothills of the Atlas. Below was a vision of such extraordinary calm and beauty that we stopped to stare: an enchanted valley hemmed in by precipitous mountains, its green floor embroidered with a broad, meandering thread of gold.

“Welcome to the happy valley,” said our guide, Mohamed Aztat, when we stepped out into this Arcadian landscape next morning. We were two families – two couples and four children aged from 7 to 14 – and ahead of us was a four-day walk up the valley and over the shoulder of M’Goun’s lower slopes. Families Worldwide, which runs this trip, rates it as a medium challenge – there are some long walks, but no sheer climbs.

There are places where the notion of trekking with children is a nightmare, but Morocco shouldn’t be one of them. No country I know is so well set up for family adventures. The secret lies in the simplicity of the arrangements – and the availability of mules.

In the mountains here, these beasts are the only viable way to carry loads, so the more remote you are, the easier it is to find four-legged transport. What’s more, muleteers find lugging camping gear for walkers a good earner, and a break from the drudgery of carting supplies for locals. Our muleteers were especially happy, as we’d arranged for their mules to be lightly loaded so they could also carry tired children.

We spent the night in Agouti, the sort of village where nothing stirs between sundown and sunrise. Our gîte was basic but manageable. As in the old Toubkal days, we slept on mattresses on the floor.

Next morning, while the mules were loaded, we walked ahead along a track that followed the Ait Bougmez river. The valley was hemmed in by sheer rocks, but ascents were gentle and our trickiest challenge was to cross the river as it swung across the plain. Hopping over stepping stones kept the kids amused, and the sure-footed Mohamed Aztat ensured they made it without mishap.

By mid-morning the sun had warmed the valley, and the younger children were beginning to tire. Right on cue, the mules caught up and the kids climbed on. There were no saddles, but our mattresses, laid over the mules’ wicker baskets, made for a cushy ride, and the children’s spirits revived as they moved ahead of us.

A couple of hours later, we found them throwing sticks into the river, the mules unloaded, mattresses spread, and the cook preparing a lunch of salads, eggs, tuna and bread. We were less than 48 hours from home, yet already in remote, mountainous Morocco. The landscape changed repeatedly during our walk that afternoon. At times, we clambered through narrow gorges with barely space for a path between the river and the rock walls that contained it. At others, we spread out across broad, green fields, beneath trees that Mohamed identified as walnut and juniper.

As the sun dipped soft and low, we began a steep final pull up to Rougoult, and the children’s weariness disappeared as they realised that this village had no gîte – we would be camping. No camp site, either, so we pitched the tents in an idyllic, tree-trimmed spot near the river. Local kids came to watch, and the various children eyed each other while Mohamed unveiled the first of his surprises, a large mess tent. It could rain at any time up here, and he knew from experience that nothing made foreign walkers more miserable than ending a long day with a damp dinner. After we’d eaten, he revealed the second neat touch, the “bathroom” – a small, man-sized tent with a toilet seat and a long drop.

There was something unexpectedly satisfying about walking up out of the Ait Bougmez valley the next day. I had been prepared for the beauty, the wildness, the challenge of climbing long slopes on city legs. But I hadn’t anticipated the fundamental joy you get from following a river through tight gorges, winding gullies and sharp ravines to its source – which in this case turned out to be on the lower slopes of Jebel M’Goun.

The source was a slit on a slope at about 9,000ft, from which water seeped down towards the valley. We reached it in time for lunch, to find our chef had got ahead of us and put up the mess tent to keep us warm – there was ice at this height. I couldn’t resist putting my head down for a postlunch nap.

However grand the Ait Bougmez had been, the panorama beyond the pass, down the Tessaout valley, was even more dramatic – a vast, primordial landscape that looked as if it was still being formed. Such immensity, we all agreed, tends to put life, its problems and obsessions into perspective. We walked down towards the first village with a sensation of overwhelming joy.

The Ait Atta, the tribe who live here, have responded to the grandeur of their valley by studding its slopes with remarkable houses, animal pens and fortified granaries, all built using materials found within walking distance, and therefore in perfect harmony with their surroundings.

This architecture is so pure, so exceptional, that in one village we came across a professor of architecture from Rabat university, bringing his students to observe construction techniques that haven’t changed in centuries. He said they were only to be found here and in remote parts of Yemen and Afghanistan.

The rogue colours in this world of blacks, beiges and greens were occasional clumps of irises and the multi-patterned clothes of the young girls who ran ahead to alert their families of our coming, or walked alongside holding our hands, beaming at this simple contact.

All the way, Mohamed interpreted for us – not just the Berber dialect, but so much else: the region’s geology, the properties of plants, the best way for our children to catch frogs, how corn is ground . . . and a thousand other differences in the life and thinking of the lucky people who live in the happy valleys that slope down towards what now seemed a more comfortable but much less extraordinary world.

On our final night, we shared a larger gîte with another group of foreigners, and had electricity for at least some of the evening. By then, the children were sufficiently familiar with their new environment to run around with the village kids. They came from different worlds, shared no language in common, but that didn’t stop them playing tag through the village, running between houses and leaping over rocks as though they’d lived there all their lives.

We had experienced four days of remarkable landscapes, of walking up one river and down another, of seeing no other trekkers. The M’Goun had more than lived up to its reputation for being remote and rewarding. But for how long? Mohamed has had more people asking about walking here. And, as we saw when we finally reached tarmac the next day – our legs heavy, our hearts more so – the Moroccan government is encouraging visitors by improving the little-used road over the Atlas.

Before long, no doubt, coach parties will pop over from Marrakesh for lunch, Richard Branson will buy a kasbah, there will be beds in the gîtes and it will be impossible to walk far without bumping into your neighbour. For now, though, this is where to find the back of beyond.

Anthony Sattin travelled as a guest of Families Worldwide

Travel details: Families Worldwide (0845 051 4567, www.familiesworldwide.co.uk ) offers a tailor-made sevennight tour in the M’Goun region, with three nights in Marrakesh, four nights’ guided trekking and transfers, but not international flights, from £495, full-board (£395 for children). Mohamed Aztat runs treks in the M’Goun and elsewhere in Morocco (00 212 68 76 01 65, http://toubkl.guide.free.fr).

Other companies to try include The Adventure Company (0845 450 5312, www.adventurecompany.co.uk ), Discover (01883 744392, www.discover.ltd.uk ), Explore (0870 333 4001, www.explore.co.uk ) and Original Travel (020 7978 7333, www.originaltravel.co.uk ).

British Airways (0870 850 9850, www.ba.com ) flies to Marrakesh from Heathrow; from £132. EasyJet (www.easyjet.com ) flies from Gatwick; from £84. Other carriers include Atlas Blue (www.atlas-blue.com ) and Royal Air Maroc (020 7307 5800, www.royalairmaroc.com ).

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