Nigeria, in West Africa, has ancient urban traditions and a complex hierarchy of urban centres. Lagos, in the south-west corner, is by no means its oldest city, and is no longer its administrative capital; but it is several times larger than Nigeria's other major cities, and indeed it is the largest in Tropical Africa.

No reliable population figures exist, all censuses having been disputed, but UN estimates indicate that by 2000 the total for the Lagos agglomeration had reached 13.4 million, making it the world's seventh largest city. These UN figures also show it to be the fastest growing metropolis, for in 1990 it ranked only 21st with 7.7 million inhabitants, while it is projected to be the world's third largest city, with over 20 million, by 2010.

These UN estimates, and the implied 6% annual growth rate for the 1990s, may well be exaggerated. The 1991 census recorded only 5.3 million in the area generally taken as the Lagos agglomeration, while other estimates for 2000 range from 9 to 14 million. As in any city there is uncertainty about the outer limits of the agglomeration, but here there is no problem of cities merging into a conurbation. Lagos State, now one of 36 states in the federal republic, has no other cities: the nearest large city, Ibada, lies 130 km to the north of Oyo State. Even though prospects for conducting a reliable nationwide census remain remote, there is a strong case for attempting a new census for Lagos.

The city's heart occupies a small island beside a channel linking extensive lagoons to the Atlantic Ocean, but it now spreads across about 800 km2 of the surrounding low-lying mainland. In some core areas population density now exceeds 200,000 per km ², and overall it exceeds 20,000, even though much housing is of only one storey and large areas are devoted to industry and transport. Public open space is very limited in extent, and even urban agriculture is less widespread than in many African cities.

For a more detailed description of the image click "View".