The World's Ten Biggest Metropolitan Areas

1. Tokyo, Japan
Metropolitan area: 34 million people
City: 12.5 million people

Tokyo is by far the largest urban region in the world. Despite its size and complexity, Tokyo has a very efficient public transportation, which accounts for almost 80 percent of all daily journeys in Tokyo.

Urban Detail:
Tokyo Bay has been gradually filled up to create more space for housing and offices. Odaiba, an island entirely created out of waste material, became one of Tokyo’s most interesting tourist spots with futuristic architecture, shopping, and entertainment centers. (Photo: Miki Yokoyama)

Image 1 of 10

2. Seoul, South Korea
Metropolitan area: 23.9 million people
City: 10.3 million people

Seoul has grown rapidly since the Korean War (1950-53). Today, nearly half of the country’s population lives in Seoul and its surrounding area. In recent years, Seoul modernized the city’s transportation system and created more public green spaces.

Urban Detail:
Foreign direct investment in Seoul has dropped about 20 percent since 2000. Many companies dread South Korea’s restrictive regulations on foreign investment, its government monopolies, and strict immigration rules. (Photo: Reuters)

Image 2 of 10

The World's Ten Biggest Metropolitan Areas

3. Mexico City, Mexico
Metropolitan area: 22 million people
City: 8.7 million people

Mexico City is ten times the size it was in 1940. Now with about 22 million people in the metro area, the Mexican capital generates almost a quarter of the country's wealth. However, with a low population growth of 0.99 percent, the number of people in retirement is expected to rise rapidly in the next decades.

Urban Detail:
Security, air pollution, and traffic congestion are prime concerns in Mexico City – problems that result from poor resource management and unstructured growth. (Photo: Reuters)

Image 3 of 10

The World's Ten Biggest Metropolitan Areas

4. New York, United States
Metropolitan area: 21.9 million people
City: 8.2 million people

New York City, especially Manhattan, is a role model for balancing dense development with good public transport and access to open spaces. Different in many regards, New York City is the only U.S. city where most households do not own a car.

Urban Detail:
New York City has been a major point of entry since the first immigrants came to the United States. Over 170 languages are spoken there today. No single nationality or ethnicity dominates the city’s exceptionally cultural diverse population. (Photo: Reuters)

Image 4 of 10

The World's Ten Biggest Metropolitan Areas

5. Mumbai, India
Metropolitan area: 21 million people
City: 13 million people

Mumbai – known as Bombay until the name was officially changed in 1995 – is the most densely populated city in the world. Through high birth rates and a perpetual influx of migrants, Mumbai’s population is expected to grow by one fifth in the next ten years.

Urban Detail:
Over half of the city’s population is still living in slums. Poor infrastructure and widespread poverty make it very difficult to meet the demands of an ever-growing population. (Photo: Reuters)

Image 5 of 10

The World's Ten Biggest Metropolitan Areas

6. Sao Paulo, Brazil
Metropolitan area: 19.6 million people
City: 11 million people

Sao Paulo, the sixth-largest metropolis in the world. It is Brazil’s richest city and the most important financial center in Latin America. Poverty and crime, however, remain a problem. An average of 6,000 people are murdered annually.

Urban Detail:
With more than 66 percent of its population under twenty years and many immigrants, Sao Paulo is a very young and ethnically diverse city. (Photo: Shutterstock)

Image 6 of 10

The World's Ten Biggest Metropolitan Areas

7. Los Angeles, United States
Metropolitan area: 17.9 million people
City: 3.9 million people

Los Angeles is the second biggest city in the United States by land size. An extensive grid of freeways, boulevards, and smaller neighborhood roads spans the city.

Urban Detail:
Los Angeles is home to the largest Mexican, Guatemalan, and Korean population outside of those countries. Almost 40 percent of the city’s population was born outside the United States. (Photo: Reuters)

Image 7 of 10

The World's Ten Biggest Metropolitan Areas

8. Shanghai, China
Metropolitan area: 17.8 million people
City: 9.8 million people

With China’s growing gross domestic product and economic strength, Shanghai has become the financial and commercial center of the country with one of the world’s busiest ports and the world’s most extensive bus systems with nearly one thousand lines.

Urban Detail:
Shanghai is a relatively homogenous city, with only 0.7 percent of its population born outside of China. Shanghai’s population growth is mainly powered by inward migration from rural areas, also called the "floating population." (Photo: Reuters)

Image 8 of 10

The World's Ten Biggest Metropolitan Areas

9. Jakarta, Indonesia
Metropolitan area: 15 million people
City: 9.3 Million people

Jakarta had to suffer major setbacks in the past decade due to the economy crisis in 1998 and natural disasters like floods and earthquakes. Since 2005, Jakarta has made an economic recovery, boosting Indonesia’s economy to a robust growth rate of 6 percent.

Urban Detail:
Many parts of Jakarta’s biggest river, the Ciliwung, are heavily polluted and clogged with garbage, strongly affecting the city’s environment and its surroundings and causing serious damage to the coastal ecosystem. (Photo: Reuters)

Image 9 of 10

The World's Ten Biggest Metropolitan Areas

10. Moscow, Russia
Metropolitan area: 13.4 million people
City: 11.3 million people

For the second time in a row, Moscow was named the most expensive city for expatriates in 2007. With more passengers than New York City and London combined, Moscow has the world’s busiest metro system serving more than nine million people a day.

Urban Detail:
Despite Russia’s capital getting richer, its population has been declining due to low birth rates and short life expectancy. (Photo: Reuters)

Image 10 of 10