Visitors to Cairo are often vexed by a pressing question. How, they wonder, does this city survive? The answer is that it doesn't just survive, it thrives. But don't push too hard with the hows and whys.

For one thing, don't trust any numbers. Egyptian statistics are charmingly vague on the whole, but the figures for Cairo are vaguest of all. Everyone knows Egypt's capital is a great, teeming, ramshackle metropolis, the biggest Arab or African city by far. But does it house 10m people, or are there 12m or even 14m? No one knows for sure.

Who feeds all these people? Is it the 20 per cent or 30 per cent or perhaps 40 per cent of Cairo's labour force working in the black economy? Whatever the total, their incomes are not enough to keep a quarter - or is it a third - of households out of serious poverty? Yet, despite the hardship, Cairo is said to be the safest big city in the world, after Tokyo. Sadly, crime seems to be rising. But is it really, and by how much?

Such conundrums don't exercise Cairenes themselves. Their city has changed at such a breathless pace that the freeze-framed world of numbers makes little sense anyway.

It is not just that what were fields and farming villages a generation ago have been engulfed and overwhelmed by construction. The rhythm of life has speeded up radically. Working hours have lengthened. Tempers have shortened. Under the press of a chronic housing crunch, extended families that lived for generations in one neighbourhood have dispersed across the city.

Underground trains and overpass roads have cut back some commuting times. Yet, the surge in the number of cars to somewhere beyond 1m has slowed other arteries to the pace of the donkeys that served as mass transit (very efficiently, by all accounts) in medieval times, when the city already endured such plagues as polluted air, uncollected garbage and - yes - traffic jams.

Then there is the question of which Cairo we are speaking of. One version of the city has always been Egypt's showplace, and not just because of ancient pyramids and medieval mosques and palaces. A hundred years, ago Cairo already boasted such "modern" metropolitan trappings as an opera house, tree-lined avenues and public squares with heroic statues, and a wonderful zoo.

Rather self-consciously, it still has all today's municipal prerequisites: a ring road and a metro, a World Trade Centre and an International Conference Centre where businessmen shout orders into cellphones. Like every globalised city, Cairo boasts a downtown waterfront rimmed with tall buildings as well as sprawling suburbs with automatically sprinkled lawns.

But there has always been another Cairo, the one where most people live and work. This is a place of narrower horizons, both physical and personal. Its lanes and allies, cramped apartments and shoe-box workshops are congenial places in a crowded, friendly sort of way, but life there is also tough.

There is little privacy in the so-called popular quarters. Public sanitation, health and education are atrocious. There is not much for young people to do, particularly with unemployment running at 9 per cent. (That's according to the government. Independent estimates range from 11 per cent to as high as 20 per cent.)

Cairo's two cities together form a chaotic quilt. Mudbrick villages sit stranded amid high-rises where penthouse flats cost $1m and more. Flyovers loop around medieval mosques. Raw brick tenements so freshly laid that their reinforcing rods still poke skywards, surround crumbling villas that were once the country retreats of pashas and courtesans.

In the mostly peaceful contest between Cairo's two halves, it is the city of the poor that has long been gaining ground. Feeble zoning rules have allowed once-exclusive districts to be shabbified by haphazard building, even as their original cosmopolitan inhabitants drifted away in the great tide of emigration that followed the 1952 revolution.

Suddenly, however, there has been a sea change. The cautious economic boom since 1992 has not yet prompted gentrification of Cairo's faded older quarters. Instead, it has pushed Egypt's capital to break its old natural boundaries, the desert cliffs that closely hem the Nile Valley.

To the east and west of the city, private developers are transforming vast tracts of desert waste into prosperous-looking residential suburbs.

In fact, the surge in suburban development has as much to do with politics as with economics. Until 1990, the government itself - as owner of all Egypt's deserts - monopolised desert building. According to its five-year plans, Cairo was to be ringed by a green zone of parks, beyond which there would be a series of Stalinist dormitory villages serving satellite factory towns.

Only a few of the housing blocks were actually built, however, before a new housing minister arrived, binned the plans and privatised the lot.

In short order, Egypt's richest men and institutions have snapped up an estimated 50,000 acres of peri-urban desert. Nearly all have opted to invest in building themed and gated communities of luxury housing.

If all the developments succeed, the geographical area of Cairo will double within 15 years and the lifestyle of the city, with its congenial mingling of classes, may change for good.

Not only are most of the new desert suburbs walled and guarded, many are even divided internally. The $500,000 mansions are closed off from the $250,000 semi-detached houses, and so on down a strict hierarchy. At Sunset Hills, there is actually an underground quarter where servants can live among the parked cars and laundry rooms, and never be seen unless called for.

Yet Cairo's poor should not give up hope. If the economy keeps ticking over as at present, they will not be so poor in a few years. On the other hand, the city's history is peppered with similar tales of pharaohs and sultans building walls to shut out the poor. Every time, the walls were breached within a generation, or maybe two.

Max Rodenbeck is a journalist and authorof Cairo: The City Victorious


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