This work is an exploration of the nature of the city from its beginnings to contemporary Cairo, the largest city the world has known. "Cities" explores the city's "raison d'etre", functions and forms, its achievements and problems, from fortifications to sewers, factories to markets, theatres and bars.From the ruins of the earliest cities to the 21s t century, the book explores how cities develop and thrive, how they decline and die, how they remake themselves. It investigates their parasitic relationship with the country around them, the webs of trade and immigration they inhabit, how they feed and water themselves and dispose of their wastes.