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Estimations -

Before we really jump in, we should mention that the numbers listed here are only rough estimates, considering these are urban areas with population densities that cannot be easily measured. As such, this list may be incomplete.

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Manshiyat Naser, Egypt -

This slum, also known as "Garbage City," is located in the western area of Cairo, Egypt. Most of the 70,000 residents of this informal settlement are garbage collectors, hence the name.

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Manshiyat Naser, Egypt -

This part of the city most prominently lacks infrastructure and appropriate running water, despite the fact that the area has shops and apartments.

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Paraisópolis, Brazil -

The neighborhood of Paraisópolis can be found in the city of São Paulo, located in the south of Brazil. The slum is the largest informal settlement in the city, with estimates placing the population at almost 100,000.

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Paraisópolis, Brazil -

This type of informal settlement is called a favela by locals, and the name of this particular settlement translates to "Paradise City."

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Khlong Toei, Thailand -

This slum can be found in the Thai capital of Bangkok. With an estimated population of 150,000, it is also the most populated informal settlement in the entire country.

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Khlong Toei, Thailand -

The slum covers an area of approximately 0.54 sq mi (1.4 sq km), and is most known for its fresh market, which is the biggest in the city.

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Makoko, Nigeria -

Nestled in the city of Lagos is Makoko, sometimes referred to as the "Venice of Africa" due to its myriad of waterways. This slum has an overwhelming population of almost 300,000, most of whom are fishermen.

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Makoko, Nigeria -

Interestingly, one-third of the community of Makoko is constructed on stilts above the lagoon, while the remainder sits on solid ground.

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Alexandra, South Africa -

Spanning more than 2.67 sq mi (6.91 sq km) in the city of Johannesburg, this slum is one of the poorest urban areas in South Africa. It is also one of the most densely populated, with almost 300,000 people living in this small area.

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Alexandra, South Africa -

Alexandra is considered one of the most dangerous places in the country. Indeed, the slum has been the central location for many xenophobic attacks.

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Cité Soleil, Haiti -

Also known in English as "Sun City," this impoverished slum can be found in the metropolitan area of Port-au-Prince in Haiti. Almost 400,00 people live in an area that is roughly 8.5 sq mi (22 sq km).

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Cité Soleil, Haiti -

AIDS and violence are major contributors to the slum’s extreme mortality rate, which has also worsened due to earthquakes, flooding, and cholera.

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Khayelitsha, South Africa -

Another South African slum joins this list, this time located in the coastal city of Cape Town. Khayelitsha is one of the fastest growing informal settlements in Africa, and its population of 500,000 people reside in an area of 14.95 sq mi (38.71 sq km).

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Khayelitsha, South Africa -

In the local Xhosa language, the slum’s name means "New Home," although this optimistic name is only part of a long history involving racial segregation and economic hardship.

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Mathare, Kenya -

A collection of slums known as Mathare can be found in the Kenyan capital city of Nairobi. In total, their population spreads over 500,000 people.

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Mathare, Kenya -

The informal settlement has been significantly damaged in the past by gang violence, and police have been known to retaliate in significantly lethal ways.

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Petare, Venezuela -

Located in the Venezuelan capital city of Caracas, the Petare slum is one of the largest in Latin America; it houses an estimated 700,000 people.

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Petare, Venezuela -

The community of Petare has often been characterized by its vibrant street life and bustling vendors, most of whom are unable or unwilling to make money by other means.

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Tondo, Philippines -

Tondo slum is located in the northern part of Manila and is one of the most densely populated areas in the city, with estimations placing the total population at about 700,000.

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Tondo, Philippines -

Like most of the informal settlements on this list, Tondo’s residents often build their homes from scavenged materials, such as corrugated metal and plywood.

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Kibera, Kenya -

Here is another slum in Kenya’s capital city. This is the largest urban slum in Africa, with a population of almost a million located in Nairobi.

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Kibera, Kenya -

For the past 15 years, the Nairobi government has attempted to build infrastructure and housing for locals. But due to political and financial unrest, officials have estimated that it will take 1,178 years to complete!

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Dharavi, India -

Possibly one of the largest slums in the world can be found in Mumbai, India. It is home to more than a million people, and has an active informal economy with a turnover of more than US$1 billion every year.

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Dharavi, India -

Dharavi has been the site of many epidemics and natural disasters, which often result in significant loss of life.

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Neza-Chalco-Itza, Mexico -

Mexico City is home to Neza-Chalco-Itza, an informal settlement that houses almost two million people.

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Neza-Chalco-Itza, Mexico -

Also known simply as Neza, the overall city was famously built on top of a lake that was drained incrementally over the course of several hundred years.

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Sadr City, Iraq -

Formerly known as "Saddam City," this informal settlement is home to over two million people in the city of Baghdad, predominantly Shia Muslims.

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Sadr City, Iraq -

For the past 15 years, a consortium of contractors have been attempting to reconstruct Sadr City so that a quarter of the residents would at least have sufficient housing.

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Orangi Town, Pakistan -

The most populated slum in the world is located in the city of Karachi in Pakistan. It holds an estimated 2.5 million residents over a total area of 22 sq mi (60 sq km).

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Orangi Town, Pakistan -

Although Orangi Town is classified as a municipality rather than a slum, its inhabitants are still largely from the lower class. On a more positive note, however, more than 90% of homes in the area have access to sanitation.

Sources: (Habitat for Humanity) (The Guardian) (United Nations)

See also: The most dangerous cities in America

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