Church of Saint Francesco, erected by the Benedictines and first dedicated to S. Fortunato, the church and the convent were given over to S. Francesco who, upon returning from the East, had landed in a port along the Maremma coast.
It was restored and adorned in 1231 and further embellished in 1289 by Nello Pannocchieschi. It has very simple lines. The only decorations consist of a cornice which runs along the inside of the roof, the lancet arched windows, a rose window, and an ornemental roof over the main door, with a painting of the Holy Mother and Child with Saints in the lunette; it was repainted by Casucci, who also built the bell tower, restored in 1927.
The extreme simplicity and lack of adornment of the Francescan Gothic style is emphasized by the bare brick walls. Except for the lower part of the façade, in travertine blocs, the entire construction is made of bricks turned brown over the years.
A beautiful Crucifix of great value adorns the High altar. It is attributed to Duccio di Boninsegna, and was most probably made in 1289, the year in which the church was reopened to worship. The flowing loincloth reveals the influence of Cimabue; the "S" postures of the body and the vividness of the facial expression convey resignated suffering.
The chapel on the right, which is not architectonically part of the church, is dedicated to S. Antonio of Padova. The vault and inner back wall are adorned with frescoes made between 1651 and 1680 by Francesco and Antonio Nasini.
The adjacent cloister was recently restored, together with the church. The well in the middle is known as the Bufala well. Ferdinando dei Medici had it built in 1590. On the walls there are a few tombstones with armorial bearings and remains of frescoes. In the piazza of the former hospital, next to the cloister, stands another Renaissance well, built in 1465 by the Sienese.