Staring off in a nice, clean hotel in Calcutta, everything seems quite normal and one would not be able to tell there was an urbanisation problem, but you would be wrong. Calcutta is a typical example of how problems are formed when large cities urbanise rapidly. The growth of big cities is fastest in the less developed countries, where many villagers leave the land in search of work and a better standard of living. But more often than not they find sprawling shanty towns, built by earlier arrivals, who themselves have failed to find regular work.

Calcutta is typical of such cities. Built on the wealth created by trade and industry in the period of colonial expansion, it has attracted millions of immigrants. A hundred years ago, the population of Calcutta was 630,000

Calcutta is a city built on flat, level, marshy land alongside the River Hooghly which is...