The "Forgiveness Feast", the most important religious event of the year, takes place during the spring season, followed by the Fair on the successive Monday. The
onion was one of the most important foods in the local economy (the "Castelleonesi" were famous as "onion growers"), and therefore for some years now the appointment of major attraction has become the
Festa della Cipolla ("Onion Festival"), on the first weekend in September: the feast foresees itinerant shows and gastronomic stands with curious and succulent recipes based on onion. ==References==