The first mention of a parish church dedicated to Saints Peter and Paul in Pitigliano dates back to 1061. In 1276, there was record of three parish churches: San Giovanni, Santa Maria and San Pietro, the latter later becoming a collegiate church and took the name of Santi Pietro e Paolo. It has since been rebuilt several times, most notably in 1509 by Niccolò III Orsini, count of Pitigliano.
The façade is divided into three by four large pilasters. On the side of the 16th-century travertine gate, with an 18th-century plaster depicting cherubs supporting the cross on top, there are two niches: in one there is a statue of Saint Paul and in there other is Saint Peter. The second part of the façade consists of three windows with plaster frames. The third ends with a tympanum where there is a low-relief in Carrara marble depicting the Maria Assunta with Saint Roch and Saint Francis.
The church’s appearance comes from the 18th century, when the side chapels, the baroque altar, together with architectural and decorative elements, were added. Among the works there is an outstanding vault, which has images of the four evangelists on each of its corners while in the centre there is a Glorious cross.
On the outside, on the left of the cathedral, there is a bell tower, originally used for civil and military activity. The building initially had only two orders (as shown by the municipal coat of arms of the city of Pitigliano) and a third was added in the Medici era, turning the tower into a bell tower.