ABSTRACT
Large numbers of people have lived in close proximity to each other in cities for thousands of years. e fi rst urban cultures began to develop about 5000 years ago in Egypt, Mesopotamia and India, but the size of cities and their geographical distribution expanded dramatically a er the Industrial Revolution of the previous millennium. is expansion accelerated into the twentieth century which began with 13 per cent of the world’s population living in cities and ended with a fi gure of nearly 47 per cent. Today, for the fi rst time in history, more than 50 per cent of the world’s population lives in urban areas and this proportion is expected to reach 70 per cent by 2050. In absolute terms, this global urban population was 1 billion in 1960, 2 billion in 1985, and 3 billion in 2002. By 2030 it is expected to near 5 billion (UNDESA, 2006, 2010).
