Megacities of Tomorrow

On the horizon: huge, teeming metropolises with more than 20 million people within their city limits. They will be the most densely packed megacities ever.

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On the horizon: huge, teeming metropolises with more than 20 million people within their city limits.

They will be the most densely packed megacities ever. By 2025, there will be eight such places and possibly more. Today there are none. Even more cities will grow to over 10 million -- seven in China alone. In 15 years or so, nearly 40 cities will top the 10-million mark, up from 23 now. By the mid-2020s, cities will be home to more than 70% of the global population (up from 50% now) as more people desperate for work and a better lifestyle flock in, leaving behind poorer rural areas and small towns.

Check out the world's eight most populous cities by 2025, plus a few that have an outside shot at reaching 20 million -- including one that may surprise you.

Disclaimer

Sources: McKinsey Global Institute, Siemens Green City Index,
United Nations World Distribution Prospects (2011 revision)