20 maps charting the rise of the modern megacity

How the 20 most populous urbanized areas have grown since 1990—in both physical footprint and total population.

FOO.03.20.Kabukicho Tokyo

Kabukicho district at night in Tokyo, Japan. Prisma by Dukas—Universal Images Group/Getty Images

This article is part of a Fortune Special Report on Rethinking the City.

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This article is part of a Fortune Special Report on Rethinking the City.

Over the past few decades, the population of Delhi has more than tripled, to 30 million—and the challenges of managing India’s largest metropolis have increased almost exponentially. In November, for instance, a spike in Delhi’s pollution maxed out air-quality monitors and caused flights to be diverted. Across the globe, rapidly growing megacities are grappling with similar problems, from overwhelmed sewers to crippling traffic to buckling infrastructure. According to the United Nations, the world’s urban population was 746 million in 1950, or about 30% of the total. Today some 4 billion people, more than 50% of the global population, live in cities. And by 2050, the UN projects, 68% of people will reside in urban areas. At right are the world’s 20 most populous “urban agglomerations,” as defined by the UN’s system of measuring extended city areas. Each is seeking the right blueprint for growth.

A version of this article appears in the March 2020 issue of Fortune with the headline “Plotting the Rise of the Megacity.”

More from Fortune’s special report on cities:

—Why the modern city needs a makeover
—The city that sees it all
—Can San Francisco be saved?
—5 big ideas for fixing global cities’ most daunting challenges
—Did the “techlash” kill Alphabet’s city of the future?

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