From the intricate communities under water - to those bustling in cities all across the globe.
Where people live and how they shape their environment has long been the study of urban planners. But in today's modern society - what do our choices say about us and the world we live in?
That's the topic of Witold Rybczynski's new book "Makeshift Metropolis". He joined Katty Kay in studio to discuss it.
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