Urban rail transport in Lagos, Nigeria is reviewed to understand the relationship to other modalities and the time trends. Railways were generally the first form of mass transportation, and until the development of the motorcar in the early 20th century, had a virtual monopoly on land transport. However, since about 1980, there have been significant changes in railway systems throughout the world. There have been considerable modernizing and updating of equipment to enable Railways fulfill their role more effectively. However, in Lagos, Nigeria rail transport is inefficient and has hardly developed at all over the past 100 years compared to railways in the developed world.

The advantages of rail over other modes of transport in any urban mass transportation system are un-mistakenly manifest in its ability to move tremendously large numbers of commuters at short intervals and at a relatively cheaper rate with a very high degree of safety (Oyesiku, 2004). Also, since the rails guide them, they take considerably less space than unguided vehicles; and by having their own system, trains are unaffected by such extraneous factors as traffic congestion. Furthermore, general analyses have shown that the railway consumes far less energy than its universal competitors; and while other modes of transport depend entirely on oil, the railway - depending on the choice of locomotive - can use all primary sources of energy: coal, diesel, hydraulic and electricity. It has also been noted that the rail transport disturbs the environment far less than the highway or air transport.

The problem of global warming and ozone layer depletion is one of the factors that necessitated the World Summit on Sustainable Development (WSSD) from late August to late September 2002 in South Africa. The summit commended the environmental friendliness of rail transport in mass movement of commuters in cities as well as in the minimization of urban transportation externalities like air and noise pollution, energy consumption, accidents and road traffic congestion problems. The summit established that the transport sector as a whole is responsible for approximately 25% of worldwide carbon dioxide emission; the main cause of climatic changes. The share of the rail and public transport is almost negligible while the dominant proportion of 80-90% is generated by private cars and road haulers alone (Odeleye, 2004). The summit thus recommends rail, as the backbone of sustainable urban transport.