ABSTRACT
Rapid urbanisation is a feature of the nineteenth and twentieth centuries. It first occurred during the mid- and late nineteenth century in the industrialised nations of Western Europe and North America. In Western Europe this process has slowed down during the twentieth century, although in the USA the process continues apace with the growth of the cities of the Sun Belt (the southern states of the USA from Florida to California). In the developing world, including many of the arid nations, rapid urban growth has been a phenomenon of the post-1950 period, though in some countries the process began in the inter-war period.
