Megacities

Urbanization has resulted in the development of urban settlements with very large populations. Defining the precise population of an urban settlement is challenging, as discussed in the next chapter.

The United Nations uses the terms megacity and metacity to identify very large urban settlements. A megacity is an urban settlement with a total population in excess of 10 million people and a metacity has more than 20 million people. Demographia World Urban Areas identifies 37 megacities with more than 10 million inhabitants. Eleven of the 37 have more than 20 million inhabitants, so are also classified as metacities.

Metacities and Megacities

Most of the world’s largest settlements are in developing countries, especially in East and South Asia and Latin America.

Urbanization

London grabbed the title of world’s largest urban settlement during the nineteenth century, as part of the Industrial Revolution, and was the first urban settlement to exceed 5 million, around 1900. New York held the title of world’s largest settlement briefly during the mid-twentieth century, and was the first to exceed 10 million, around 1940. Tokyo is now considered to be the world’s largest urban settlement. However, at current growth rates, Jakarta, Indonesia, may become the world’s largest by 2030.

Largest Urban Settlements 1750–2018

Jakarta, Indonesia

Possibly the next urban settlement to be the world's largest.

Developed countries may have a higher percentage of urban residents, as discussed on the previous page, but developing countries have more of the very large urban settlements. In 1900, after diffusion of the Industrial Revolution from the United Kingdom to today’s developed countries, all ten of the world’s largest cities were in Europe and North America. Now, only 3 of the 11 metacities are in developed countries—Tokyo, Seoul, and New York. And developed countries have only 9 of the 37 megacities—the above 3 metacities, plus Osaka, Moscow, Los Angeles, Paris, London, and Nagoya.

Pause & Reflect 12.4.4

How might differences in natural increase rates between Indonesia and Japan impact growth rates for Jakarta and Tokyo?

Rapidly-Growing Cities

All but 4 of the 100 fastest-growing urban settlements in 2018 were in developing countries. Five of the 13 growing at more than 4 percent per year were in Africa, 3 were in India, 4 were elsewhere in Asia, and 1 was in Latin America. The 4 in developed countries included 3 in the United States (Las Vegas, Austin, and Atlanta) plus Suwon, South Korea. The three fastest-growing urban settlements are relatively unfamiliar places: Beihai, China; Ghaziabad, India; and Sana’a, Yemen.

World’s 100 Fastest-Growing Urban Settlements

Nearly all are in developing countries.

Beihai, China

The world’s fastest-growing urban settlement is located in southeastern China, 100 kilometers (60 miles) from the border with Vietnam.

That developing countries dominate the lists of largest and fastest- growing urban settlements is remarkable because urbanization was once associated with economic development. In developing countries, migration from the countryside is fueling half the increase in population in urban settlements, even though job opportunities may not be available. The other half results from high natural increase rates; in Africa, the natural increase rate accounts for three-fourths of urban growth and migration for one-fourth.