In 1656, during the bubonic plague that devastated the city, Don Angelo Franco, the only parish priest to survive, led a Eucharistic procession from the Castle of Sant'Adiutore, blessing the Valle Metelliana. Miraculously, the epidemic receded, and by December of that same year, there were no further victims. In memory of this event, the Festivities in Honor of the Blessed Sacrament, known as the Feast of Montecastello, have been celebrated annually since 1657.
Tradition holds that each year, the procession of Corpus Christi is reenacted, with the procession featuring eight groups of "Trombonieri", the city's padri (fathers), and various flag-waving groups. These participants parade from the Cathedral Square, where they receive the Holy Blessing from the Bishop.
The month of June, during the Octave of Corpus Christi