The first nuclear reactor was built under a university football stadium

In December 1942, Enrico Fermi's team stacked graphite blocks and uranium into a squash court beneath the stands of Stagg Field at the University of Chicago. Chicago Pile-1 achieved the first human-made, self-sustaining nuclear chain reaction — with no shielding and no containment building around it.

— Richard Rhodes, The Making of the Atomic Bomb — Simon & Schuster, 1986
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