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Will there be a city on Earth with a population of over 100 million by 2100?

For a mostly hairless, fangless species that was likely reduced to just a few thousand members in relatively recent times by a volcano, we've certainly been busy.

The human population on Earth now exceeds 7 billion. And we're still growing. Not everyone is thrilled by this. But it's reality.

Currently, as of Q2 2018, Tokyo, Japan is the world's largest metropolis, cramming over 38,000,000 people (give or take) into its borders.

But by the end of the century, we could (and probably will) witness far grander cities.

Per Canadian demographers, Daniel Hoornweg and Kevin Pope, for instance, Lagos in Nigeria may swell to 100+M by 2100 if trends continue. Face 2 Face Africa has the story:

By 2100 if Nigeria’s population continues to grow and people move to cities at the same rate as now, Lagos with its current 20 million people could be home to more people than the state of California.

The demographers' full paper is here.

The International Institute for Environment and Development goes into detail about why Hoornweg and Pope are so bullish on Africa here.

Whether it's Lagos that claims the crown or some other city in Africa or elsewhere, what do you think? Will some metro hit 100M people by 2100? (For the estimate we will include the general metropolitan area rather than the strict city boundaries, as done here)

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