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The Passetto di Borgo, or simply Passetto, is an elevated passage that links the Vatican City with the Castel Sant'Angelo. It is an approximately 800-metre-long (2,600 ft) corridor, located in the rione of Borgo. It was erected in 1277 by Pope Nicholas III, but parts of the wall were built by Totila during the Gothic War.

On at least two occasions it served as an escape route for Popes in danger. Pope Alexander VI crossed it in 1494, when Charles VIII invaded the city and the pope's life was in peril. Clement VII escaped to safety through this passage during the Sack of Rome in 1527, when troops of the Holy Roman Emperor, Charles V, massacred almost the entire Swiss Guard on the steps of St Peter's Basilica.

• Index of Vatican City-related articles
• Vasari Corridor, Florence
• Passages for Maria Maddalena de' Medici (incl. the corridoio mediceo), also in Florence

• D'Onofrio, Cesare (1978). Castel Sant'Angelo e Borgo tra Roma e Papato (in Italian). Rome: Romana Società Editrice.

• Di Fiume, Mark (2000). Sogno nel Passetto? (in Italian). Bologna: Ballo Editrice.

• Augias, Corrado (2007). The secrets of Rome : love & death in the eternal city. New York: Rizzoli Ex Libris. ISBN 9780847829330.

• Curious And Unusual: the Passetto

41°54′12″N 12°27′42″E / 41.90333°N 12.46167°E / 41.90333; 12.46167