According to the Liber Pontificalis the Fire in the Borgo,
which gives its name to the room, broke out in the year 847
in the neighbourhood in front of St Peter's basilica.
Conferring his solemn blessing from the Loggia of the
Blessings, Leo IV (pontiff from 847 to 855) miraculously
extinguished the fire, thus saving the church and the people.

Credit: http://mv.vatican.va/3_EN/pages/x-Schede/SDRs/SDRs_04_03_030.html

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