The Site: In the year 590, as he prayed for Rome's deliverance from a plague, St. Gregory the Great had a encouraging vision of an angel sheathing its sword above this massive brick castle built atop the drum of Hadrian's first-century mausoleum. The plague ended, and the castle got a new name (and, in 1752, a spiffy bronze statue of the angel).
The Scandal: Castel Sant'Angelo is connected to the Vatican by the passetto, a long wall topped by covered passage allowing the pope to scurry to his stronghold in time of need—as did Pope Clement VII did during the sack of Rome in 1527. It was the only known time a Pope used the Swiss Guard as a human shield, leaving the bulk of them to die covering his escape.
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