The first record of the Church of San Pietro in Perticaia dates from 1066. Its façade is extremely simple, featuring a portal in pietra serena. Above the portal is a pointed archivolt with a niche that once held a bust of Saint Peter the Apostle.
The outer walls are bare of plaster, showing a structure formed of fileretto of alberese stone. On the outside, the entire building is surrounded by a cornice supporting the saddle roof. The cornice consists of a triple row of herringbone terracotta slats, probably dating from Renaissance times.
Inside, the church has a single nave with a semi-circular apse which once had a central single-lancet window, later bricked up and replaced with two rectangular windows. The last restoration project conducted in the late 20th century brought to light a small Early Christian crypt with an adjoining room, which is two steps lower.
On the inside are interesting artworks which were not originally here, but have come from the surrounding churches: a wooden Cross attributed to the school of Baccio da Montelupo, as well as a triptych with the Madonna and Child with Sts. Cosmas and Damian, Stephen and Anthony the Great, attributed to the so-called “Master of the Incoronation of Christ Church”.
This work, coming from the neighbouring church of Santo Stefano a Torri, was originally a triptych dating from the late 14th century; later it was squared by adding at the sides of the central body two panels depicting two angels, painted in the first half of the 17th century by the assistants of Francesco Curradi and now placed on the two walls to the sides of the apse; and at the bottom, a panel portraying four saints dating from the mid-16th century, still kept in the church of Santo Stefano a Torri.