chapter 2

• Many South American cities originated in colonial times. The Spanish crown laid down its spatial layout by law and old structures are still visible today. But the high rates of urbanisation led to new urban buildings and new urban issues or problems.
• South America is highly urbanised: on average, about 81% of the population lives in a city in 2018. The development of the cities took place in different phases and was influenced by various factors
• The arrival of Spanish and Portuguese settlers to the South American continent caused an explosive population growth. As a result, the number of cities increased rapidly.
• The Spanish crown wanted to steer the growth of these cities in the right direction and enacted laws for urban planning. Each city was supposed to have a central square with a church and government buildings. This square became the religious and administrative centre of the city. Residential areas were designated around the central square for the urban elite. The residential areas further from the centre were intended for the lower social classes.
• After decolonization in the nineteenth century, a business district was created in most cities next to the old colonial centre (see source 1), which became the economic and administrative centre of the city. Both the business district and the elite neighbourhoods were getting better infrastructure and more and more amenities, but part of the urban elite settled in new neighbourhoods outside the centre, attracted by the space and lower land prices.
• Especially towards the second half of the twentieth century, the business district expanded rapidly. Commercial zones were created along important transport axes/lines, where shops and industry were concentrated. These development corridors made an important contribution to economic development. Sometimes the government played a role in this, for example by constructing a through road.
• During the same period, large cities experienced migration from the countryside. As a result, slums sprang up on the outskirts of the city. In Brazil they are called favelas. These slums are also referred to as the informal city, as they are not part of the planned urban development. 
• Over time, living conditions in these slums improved somewhat: infrastructure and houses were renovated by residents themselves or by the government. These are called consolidated neighbourhoods. Over time, newer slums appeared on the outskirts of the city due to the stream of migrants. In general, the further you get from the centre, less and less slums are consolidated.
• The government did build social housing in some places, but not everywhere. Meanwhile, the neighbourhoods for the elite and middle class continued to expand towards the city fringes. Large shopping and office centres were also created further away from the centre.
• Nowadays, industrial areas are also emerging outside the city and shopping centres and expensive apartment complexes are being built in low-income areas on the outskirts of the city. Another recent phenomenon is that more and more people are going to live just outside the city because of the space and lower land and house prices. The surface area of the city is expanding, which has consequences for nature, the environment and the level of facilities. This expansion of the urban area and its consequences are referred to as urban sprawl
• A megacity is a city with more than ten million inhabitants. There are three in South America: São Paulo, Buenos Aires and Rio de Janeiro. Due to their enormous population, these megacities have major spatial planning problems
• Transportation

  In a mega city, millions of people and large quantities of goods are transported every day. Due to the limited space, there is a limit to the transport options: public transport is becoming overloaded and there are too few roads. The large number of means of transport - cars, trucks, public transport etc, in the city also causes traffic jams and air pollution.
• Services

  The enormous size of the population and the fact that it is a rapidly growing population also puts great pressure on facilities such as water, sewerage and waste processing. The latter also applies to the sewage system. In addition, there are often no garbage collection services in slums. The megacities must find areas for the storage of this waste and invest in waste treatment plants that can process this waste.
• Houses

  Every year the megacities grow by tens of thousands to hundreds of thousands of people. All these people need a home. In the city centre and the original residential areas there is little or no space to build new homes. Many migrants and young people are therefore dependent on building their own homes in the slums or neighbourhoods outside the city. However, it places an enormous burden on the city budget to install infrastructure and facilities for these new neighbourhoods.
• Education, healthcare and work

  It is quite a challenge to create enough educational places, healthcare institutions and jobs for millions of people. In addition, facilities must be easily accessible. If travel costs become too high, education and health care become too expensive for people, despite the fact that these services are free in some countries. Jobs in the centre are sometimes impossible for slum residents to reach because there is no public transport from their neighbourhood to the city centre.