The iconic 375 Park Avenue in New York, built in 1958 by the king of Modernist design, Ludwig Mies van der Rohe, changed skyscraper design forever.
As the world's most influential and copied tower, it has inspired the square glass blocks of every global skyline.
But behind its revolutionary glass façade is the fascinating story of how a skyscraper that couldn't afford to be built got built - and how its creator finally managed to realise his 40-year architectural dream.
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