I AM WRITING this from a town where international telephone calls are said to be darned near impossible to make and I am pretty pessimistic that anyone is ever likely to read a word of this. But why turn back now I've started? This is Siwa, an oasis deep in the western desert of Egypt. They say that an airport will be opening up soon, but in the meantime there is still only one road into the place, straight down from the Mediterranean coast to the north. From any other direction it takes days across trackless sands in four- wheel-drive cars, that is if you are lucky enough to find it at all.

Anyway, I took the road from the coast, and even that required driving fast for four hours across a desert of hot, flat brown gravel without a single blade of grass growing on it. Then suddenly here I was. Bang! Surrounded by spiky date palms and pools of water and grass and vegetables and donkeys and smiling people, 11,000 of them to be precise, living in houses of mud and breeze block.

And telephones? Sorry. But Siwa does have stuff that towns with telephones don't have. Peace and quiet, for example (the only irritating noises around here are the baying of donkeys and the crowing of cockerels). But the main joy of Siwa is its isolation, and frankly I can't see the place getting very far without it.

Because basically, the Siwans have enjoyed monopoly power in the provision of isolation and oasis services since the beginning of time. For the 2,500 years up until about 1920, if you were a merchant and wanted to cross the Sahara from north to south or east to west, you did not have any choice about where to stop en route. If you did not stop at Siwa, your camels would have died of thirst long before you had reached your final destination. It made sense. What were the Siwans for, if not to water your beasts and refill your saddlebags with dates and olives (for a small charge)? They had you in a bind and enjoyed it.

To celebrate their success, like an ancient Las Vegas, they laid on the ultimate in road-side entertainments for their itinerant guests - an oracle and a god called Zeus Ammon. Always up for a new god, the Greeks instantly fell for this one, and the fame of the Siwan oracle soon spread throughout the Mediterranean world. What reviews it got. Alexander the Great himself was to spend nine days on a hazardous desert crossing with a tiny band of friends just to have the pleasure of consulting the oracle and finding out whether or not he was the god's son. Blessed with royal approval, the Siwans looked set to enjoy monopoly profits for eternity.

Well, until about 1920 anyway, when the camel caravans more or less stopped. From that moment on, the whole point of being remote and inaccessible seemed to have disappeared in a sandstorm. Apart from dates and donkeys, what did Siwa have left over?

In fact it had tourism potential. In the context of Egypt, Siwa and its desert enjoyed, and still enjoys, a monopoly on isolation and tranquillity. It has almost no telephones. Like Alexander, latter-day Saharan caravan traders (eg French businessmen and women) will pay a big price for the pleasure of escaping to the desert - just as long as there are not too many of them. If the Siwans can only remember what their forefathers knew, they will not open their airport just yet.