London built a glass palace the size of several football pitches in nine months

To house the Great Exhibition of 1851, engineers prefabricated an enormous iron-and-glass hall in Hyde Park, erecting it in about six months. Nicknamed the Crystal Palace, it covered 19 acres and drew roughly six million visitors — a third of Britain's population — to see exhibits from across the industrializing world before being dismantled and rebuilt elsewhere.

— Jeffrey A. Auerbach, The Great Exhibition of 1851: A Nation on Display — 1999
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