Over half the world's population is now aged under 30, with the same proportion living in an urban environment. And the more youthful a city, the more friendly an environment for nurturing new businesses and technology.
The Youthful Cities Index has graded 25 of the world's biggest cities – from Buenos Aires to Berlin – from the perspective of youth, the first survey of its kind.
Cities were compared using 80 indicators across 16 categories, covering everything from diversity and civic participation, to entrepreneurship and environmental sustainability.
We took a look at the top 10 and are giving you the chance to decide which city you would like to live in.
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Clarification: This introduction has been amended to reflect the methodology used when compiling The Youthful Cities Index.