The celebration of Corpus Domini has a special significance for Bolsena, because it is closely linked to the Eucharistic Miracle happened in 1263. During the Mass, celebrated by the priest Pietro da Praga, who had some doubts regarding his faith, the blessed host began to bleed on his body at the moment of consecration and some drops of blood fell on the marble floor and on the altar steps.
To celebrate this miracle, the Corpus Domini festivity is also celebrated with traditional flower decorations, called “Infiorate”. The day of the feast begins at dawn for the Bolsena people, as they go out into the countryside to gather the flowers that will be used to set up the decorations for the traditional "Infiorata". This consists of placing a carpet of flower petals on the ground, all along the entire way of the procession in which the Sacred Stone stained by the Blood of the Miracle is carried.
The decorations made up by the colourful flower petals, reproduce artistic designs of sacred subjects, simple geometric or fantasy shapes. The route of the procession, and therefore the length of the Infiorata, is about three kilometres long.