The importance of Santa Maria in Vado is tied to the miracle of the Eucharist that ocurred on Easter Day 1171. At a moment of the consecration blood spouted from the host staining the apsidal vault above the altar. It immediately became a site for pilgrimage and by order of Duke Ercole I d'Este was enlarged from 1495 onwards with important interventions by the architect Biagio Rossetti.