Rio de Janeiro
Rio has more people living in slums than any other city in Brazil, according to the 2010 Census. More than 1,500,000 people live in its 763 favelas, 22% of Rio's total population. São Paulo, the largest city in Brazil, has more favelas (1,020) in sheer numbers, but proportionally has fewer people living in favelas than Rio.
Rio de Janeiro Metro
Rio de Janeiro is the second largest city in Brazil and the most popular tourist attraction in the country. After 1950, the number of motor vehicles on the roads increased dramatically. Rio de Janeiro lies in a hilly region, between the mountains and the Atlantic Ocean. The landscape of the city is extremely uneven, making travelling by car or bus a very time-consuming task through the narrow streets. These conditions are ideal for trams but not for the increasing traffic of motor vehicles. By the early 1960s, traffic jams, pollution, and smog had become a serious problem in the city. To overcome these problems, local transport authorities decided to reduce the tram network and switch over to a metro network.