ALI stood on the edge of what Omanis call the Grand Canyon of Arabia, pointed at a dark patch halfway up the massive canyon wall, and pronounced: "That's where you're going. That's the village of As Sab."
What? The spot he was pointing at had a 700m high cliff above and an 800m drop below. There was no way we could get there. And people couldn't possibly live in a place like that.
But they did, for several centuries, until about eight years ago when the Oman Government moved all the inhabitants to a less remote site with easier access to modern services, leaving the village to ghosts and foreign trampers.
Of course when As Sab was established, in more turbulent times, that inaccessibility would have been its big attraction.
The threat of attack meant many of the places I visited on my nine-day World Expeditions Oman Adventure were protected by massive forts. But smaller settlements had to rely on their remoteness. And As Sab must surely have been the most unapproachable of all.
I could certainly testify to the problems that would face anyone trying to even visit the place, let alone attack it. Getting there involved scrambling for over an hour along a rough, narrow path running round the wall of the canyon, often with just a few centimetres of crumbling rock separating us from a fatal drop, sometimes with piles of freshly fallen boulders signalling an equal danger above.
The extended family who once lived there must have felt the threat to their safety was very real to have come to such a barren, isolated spot. But as a consolation they did enjoy million-dollar views of the canyon from each of their humble dwellings and at every turn of the track. The Wadi Al Nakhur - the canyon's Arabic name - is a truly spectacular place which, despite its isolation, attracts visitors from all round the world.
When we arrived at the main viewing point, and Ali our driver announced proudly that this was the Grand Canyon, Gregory from Washington DC had pretended to be puzzled. "Where? Where?" he asked, looking around theatrically. Even when we stood on the brink he only acknowledged the place with a laconic, "Oh, is that all?"
Okay, he had a point, it wasn't the Grand Canyon of Arizona, but it was pretty amazing: more than a kilometre deep, the soft brown rock of its walls carved into strange and wonderful shapes, with towering cliffs stretching away as far as the eye could see.
And there, at the head of the canyon, was As Sab. When I checked it out with the binoculars, I could just see the terraces on which the village gardens were built, with a big rock overhang above and a massive slip just below. It looked terrifying. And inaccessible.
The number of people opting to walk there quickly dwindled to two - Janet from Sydney and me - and when I saw the rough, stony track disappearing over the rim of the canyon and scraping its way along the middle of the cliff face it almost became one.
But, off we set, scrambling over rock falls, climbing down natural stone staircases, pausing occasionally to admire the view or place a rock in one of the cairns built by previous travellers, two or three times getting lost but always able to regain the track because, well, there was nowhere else to go.
Occasionally we would be hello-ed by tourists who looked amazingly tiny standing on the rim high above and now and again we met a goat grazing on the sparse foliage, but otherwise there was no sign of life.
As we got closer to the village we began to get a clearer picture of the extraordinary terraced gardens the inhabitants had built up over the centuries to provide space to grow their crops and graze their goats. I can't imagine how they managed to construct the enclosing stone walls along the cliff face, fill the space behind with earth, and water it with a stone irrigation system. Even working the gardens, with an 800m sheer drop only a false step away, would have been dangerous.
Finally I came round a bend in the track and there before me was a tiny stone hut, roofed with mud and sticks, built into the cliff. Round another bend was a whole row of them. "The people who lived here must have been very small," said Janet, as she bent double to explore inside one. "These places are tiny."
Further on we came across more huts, some even smaller shelters which presumably were for goats, a row of mud storage containers built under an overhang, a couple of small stone ponds still full of water and finally the terraced gardens themselves. The soil was dry and bare but there were still a few goats happily grazing on the hardy bushes and the odd clump of grass.
I'd have been happy to explore this fascinating place for hours but all too soon we had to leave to avoid the risk of being caught on the track after sunset.
Back where our walk began, Ali was waiting with our vehicle along with some of the people who once lived at As Sab, eager to sell us small pieces of weaving and fossils collected from the crumbling canyon rock.
Sadly, their move had not ended happily. The Government built an impressive modern compound for them to live in but they weren't comfortable living there. Instead they re-created their rough shelters of stones, sticks and sheets of plastic and left the compound empty.
Worse still, having access to modern medicine led to the discovery that the males of the extended family are subject to a genetic disorder.
I felt sorry for them so I bought a few of their fossils, some for my fossil-loving grandchildren and one I've kept for myself, an appropriate souvenir of a remarkable way of life that has gone forever.
But, as I discovered, As Sab is far from unique. Many other ancient villages also sit empty as a result of the Government's campaign to bring the country into the 21st century.
At Wadi Gul, for instance, we gazed across the river at an empty village whose 400-year-old adobe houses were increasingly difficult to maintain so the Government paid for a new town to be built next door using modern materials.
At Birkat al Mawz we explored a fortified hillside village dating from the 16th century where 25 years ago most of the inhabitants decided they no longer needed walls to protect them and moved to the fertile river flats. Some families were clinging on - a father and his two sons were busy planting date palms in a small courtyard - and a few homes had been patched with concrete. But several of buildings were starting to fall down.
And at Ibra, a much larger settlement, majestic empty homes in what was once the most well-to-do suburb are now being restored with the help of Unesco.
"This," Ali told us as we walked between the crumbling walls of the main street, "was my mother's home. Very rich people lived here. Each house had its own well, they were very beautiful" - he pointed through the gaping windows to draw attention to the ornate carving and painting on the walls and ceilings - "and very well built."
So what happened? "The houses were built on coconut palm piles but they do not last forever and 25 years ago the foundations started collapsing."
What about his mother? "She lives with me in Muscat. But my uncle still lives here. Over there. He doesn't want to leave. He prefers this way of life."
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