Nowadays, there is an indictment of big cities. In France, the development of urban areas is blamed for population drain , tear of social ties ; in the United States, cities mean violence and drugs; in Germany, cars, imperative in town, are responsible for pollution.Does it mean that the death of big cities is, as it must have happened in Babel, inevitable or even desirable? To answer, François Ascher analyzes and assesses the actual tendancy to concentrate men, activities and wealth.