The Hanoi Hilton reference article from the English Wikipedia on 24-Apr-2004
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Hanoi Hilton

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During the Vietnam War, Americans taken as prisoners of war by the North Vietnamese were interned in Hoa Lo prison, built by the French in 1901. The conditions there were so miserable, and the food so bad, they ironically nicknamed the place the Hanoi Hilton, and it was used as a place for the North Vietnamese army to torture American prisoners. This was depicted in the Hollywood movie, Hanoi Hilton. The prison was never actually affiliated with the Hilton Hotel chain.

Senator John McCain was a prisoner at the Hanoi Hilton. Currently there is a hotel in Hanoi with the same name (owned by Hilton).