Feast of St. Petronius in 2025

When is the Feast of St. Petronius?

The Feast of St. Petronius is a regional public holiday in the northern Italian city of Bologna observed on October 4th each year.

This holiday takes place on the feast day of the city's patron saint.

Traditions of the Feast of St. Petronius

Today Bologna is one of the largest and wealthiest cities in Italy, though if you had arrived in Bologna in the first half of the 5th century, you would found a city on the decline.

Bologna (from "Bononia," Latin for "the Beautiful") was a central hub along the Italian peninsula but had lost its sheen after being abandoned by the Romans. To make matters worse, many buildings had been destroyed by the Goths during their invasion of the collapsing Western Roman Empire.

In 431AD, Petronius arrived in Bologna to become the 8th bishop of the city. Born in Gaul (modern-day France) to an affluent Roman family, Petronius had converted to Christianity and travelled to Jerusalem before becoming a priest and arriving at his new post in Bologna.

Petronius was bishop for the next 19 years and in that time, he became revered for his repair of many buildings, restoring some of the former glory to the city. He also built the monastery of St. Stephen (Santo Stefano).

Showing an impressive skill at marketing, he based the church of St. Stephen on the design of Jerusalem’s Holy Sepulchre, the shrine, built by Emperor Constantine, where Jesus Christ is believed to have been crucified and buried.

Legend has it that Petronius did this to attract Christian pilgrims to Bologna to see his version of the Holy Sepulchre, as an alternative to making the expensive, arduous and dangerous pilgrimage to the Holy land to see the real thing.

Petronius also imported relics from the Holy Land. Christian relics appeared in most mediaeval European cities as a way of attracting more visitors and increasing the prestige of the city which housed them.

His relics included a bowl, which is said to be where Pilate washed his hands of Christ’s trial.

Nowadays the most important church in Bologna is the one built in his name. The Basilica of San Petronio is one of the largest churches in the world. It was planned to have been even larger, but it was intentionally kept smaller so that St. Peter's in Rome would be bigger - as some compensation, it does house the longest indoor meridian line in the world!

Arguably his most important legacy is not his building work, but his charitable work for Bologna's poor, whom he provided with food and money.

On this feast day, some shops may be closed. A service to celebrate Saint Petronius is celebrated by the Archbishop in the Basilica in the evening with a religious procession between St.Peter's and St. Petronio's.

Note that Petronius doesn't have October 4th to himself; it's also the feast day of St. Francis of Assisi.