Chiesa dei Santi Pietro e Andrea Trequanda

As can be read in the plaque placed next to the chapel of the SS. Sacramento, the first stone of the building was laid by the apostolic legate of John XXII in the year 1327; probably it was the extension of a much older sacred building, as can be assumed from the structural and decorative peculiarity of the façade of a clear Romanesque period and as can be seen from the ancient chronicles: here probably already stood in the twelfth century a temple dedicated to the Madonna, in which the pleban rights of the ancient Pieve di S. Andrea were transferred.

The original facade of the Church is built by alternating ashlars of travertine and tufaceous stone, in the shape of a chessboard; in the center the large rose window with a mosaic stained glass window reproducing the face of the Blessed Bonizzella.

The interior of the church is a Latin cross with a single nave. The ceiling, originally with wooden trusses, was rebuilt in 1875 with ribbed vaults with pendentives supported by pointed arches set on pilasters, while the cross vaults of the transept, ribbed in brick, are original.

The building contains works of considerable artistic value.

One of these is the splendid wooden urn, full of frames and ornaments carved in bas-relief, in walnut highlighted with gold, a work of Sienese art from the 1500s. The urn contains the remains of the Blessed Bonizzella Cacciaconti, noblewoman of the powerful and ancient family of feudal lords. Ghibellines who ruled these lands. She married Naddo Piccolomini, a Sienese Guelph, left a widow, she settled on the beautiful farm of Belsedere, dedicating herself to prayer and charity. After a series of miraculous vicissitudes, her body was transferred to the main altar of the Church and here she has been venerated as a Blessed for centuries. The Trequandino people are tied to her with affection and solid faith.
The Church also preserves the Polyptych by Giovanni di Paolo di Grazia (1399-1482), the remarkable fresco of the Madonna and Child enthroned and the saints Catherine of Alexandria, Mary Magdalene, Giovanni Battista, Bernardino da Siena, by the Umbrian painter Bartolomeo da Miranda from 1449, the fresco of the Ascension by Giovanni Antonio Bazzi known as Sodoma.

Another preserved masterpiece is the oil table of the small urn containing the remains of Blessed Guido, grandson or son of Blessed Bonizzella. A niche on the left wall contains the beautiful colored terracotta group of the Madonna and Child attributed to Andrea Sansovino; the canvas of the Madonna del Rosario, the Sienese school fresco (15th century) depicting Sant'Agata holding the sign of martyrdom and the pipe organ from 1840, conclude the brief and incomplete review of the treasures kept in the Church.