The sanctuary was built between 1590 and 1625 by the architect Pietro Cecini to honor an image of the Mother of God, which was visited every night by hosts of angels. In 1612 the image was placed above the main altar. Inside there is a majestic dome with a paradisiacal setting by Luigi Ademollo from the 19th century. The Milanese painter also created paintings on the sides and above the main altar. Every year on September 8th, the feast day of the Nativity of the Virgin Mary, Pieve Santo Stefano celebrates the feast of the Madonna dei Lumi. This tradition began on September 8, 1631, the year in which the population, through the voice of their priest Pietro Strozzi, made a solemn vow to celebrate the Nativity of the Blessed Virgin every year if she would deliver the country from the plague.