For Rem Koolhaas and Miuccia Prada, more is more. A luxurious tower of art galleries is the last building on the Prada Foundation’s campus.

I kept running my hands over the tower’s concrete walls. Infused with Carrara marble and poured by construction workers who wore white gloves, they feel smooth as silk. The big rectangular and wedge-shaped galleries, windows alternating between panoramas of the city and narrow views over the campus, accommodate best the large-scale works in the inaugural show

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