A drive through the Atlas mountains is not for the fainthearted. But Adrian Mourby and his son are made of stern stuff

They were studios that looked as studios should look. Huge Egyptian figures lined the outer wall. What's more, the Oscar Hotel was open for coffee. When the likes of Russell Crowe and Orlando Bloom are not in residence the hotel opens up its Gladiator bar and Cleopatra restaurant.

So I treated John to a soft drink and we wandered round sets and props with stars in our eyes: past Michael Douglas's plane in The Jewel of the Nile; a Tibetan house from Martin Scorsese's Kundun. There was a mock-up of Cleopatra's palace, which looked decidedly unregal after recent rain. On the horizon we could make out the set for Jerusalem in Kingdom of Heaven. It was cold and damp, but that didn't stop John wanting to linger.

I had promised him another adventure: an ascent of the mighty Atlas Mountains, which were all that now stood between us and the Atlantic. That we'd be passing over peaks formed millions of years ago by the collision of Africa and America fired my imagination, but my teenage son was unconvinced. Anyway, I pointed our car in the direction of Marrakech.

With snow-topped mountains looming, we were soon passing elaborate roadside pottery stalls offering brightly glazed tajines to non-existent traffic. At Tatzoune we turned right, following signs to Ait Ben Hadou, an authentic Berber village used in Lawrence of Arabia and Jesus of Nazareth, and which is on Unesco's world heritage list.

We rose rapidly to the Tizi n' Tichka Pass, 2,610m above sea level. The receptionist at our hotel had been cagey when I'd enquired about the weather up there. It was, she said, impossible to predict and the altitude meant that the rapidly changing conditions could make driving quite hairy. Our last chance to back out came at a road sign pointing south to Agadir. It started to rain and as I engaged a lower gear, the valley ahead became steep and narrow. We passed stone dwellings sunk into dank, black soil and soon the roads were in flood. I turned the windscreen wipers on to maximum speed, hoping to convince us both that this would keep the elements at bay.

"Snow," said John, and soon the windscreen was being covered by large, white flakes. When the wipers couldn't shift them quickly enough, I wound down the window to see where this damn road was going. The first thing I saw were some cold, wet salesmen selling crystals dyed in unconvincing colours. The higher we climbed, the more desperate they became, occasionally stepping across the road as I swerved, swearing violently.

We stopped for refreshments and I tried again to clear the windscreen. "Right. All downhill from now on," I told John, trying to reassure him as he strapped himself in. Unfortunately, I was right. As we dropped into the Ghdat Valley our puny hire car stalled. After so long in low gear the engine had overheated. I got it going again but after I braked suddenly to avoid a flood, it cut out completely. "Never mind, Dad," said a white-faced John.

When the car re-started, it would only move in low gear, making me unpopular with drivers keen to get to Marrakech by nightfall. The rain stopped and when the sun came out, we could see a beautiful green valley below. Too far below for comfort, mind, but beautiful nevertheless. I switched off the engine and we rolled for what seemed like hours, coasting to a halt next to an olive grove. I pulled on the handbrake. Life seemed unbearably wonderful. "Well, that was fun," I tried telling John. "It was an adventure," he conceded, "but the best bit was realising we weren't going to die." Sometimes you can give your child too good a time.

The author travelled as a guest of British Airways (0870-850 9 850; www.ba.com), which offers return flights to Marrakech and Fez from £129 return