For the first time in human history, the majority of the world's population
live in cities. At the same time, the number of people living in urban slums
has passed the one billion mark; every third person living in a city is a
slum dweller. The United Nations projects the world's urban population to
grow by two billion before 2030. More than 90% of this growth will take
place in the least developed countries, and it will be concentrated in the
bleakest parts of their cities.
The Kibera slum is located five kilometres south west of Nairobi's city
centre. One million people are crammed in to a piece of land the same size
as Manhattan's Central Park. Christian Als spent three years documenting the
lives of people in Kibera.