Cairo is a lodestone of civilization, the center of a complex field of geographical, historical and cultural currents compressed into one chaotic megalopolis on the banks of the Nile. Egyptians proudly refer to their capital as the "Mother of all Cities." Medieval Arabs called it the "Mother of the World." For centuries it has been a natural meeting point between African, Arabic and European cultures. To walk through Cairo -- from the pyramids at Giza, via the Roman-influenced old town, the mosques and souks of Ottoman-era Darb al-Ahmar, the Garden City's Art Deco suburbs to Nasser's secular modernism -- is to step along a seismic fault line of epochs and empires. Yet in its modern incarnation, Cairo inspires more awe than love. Overcrowded, overflowing and overstretched, Cairo is home to more than 16 million people, with an estimated 13 square centimeters of greenery for each of them. As the suburbs begin to creep around them, even the pyramids are no longer sacred space. Away from the tourist routes, biblical slums spill out into the desert. A third of Cairenes live without running water and a quarter manage without sewers. Dusty, polluted, noisy and snarled up with traffic, even Downtown Cairo can be a violent culture shock to western sensibilities. Yet somehow the city continues to function, held together primarily by a complicated mosaic of customs and tradition that outsiders can only scrape the surface of understanding.
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