Built at the end of the 13th century on the ancient church dedicated to Saint John the Baptist, it stands on the highest place in the city, where it was certainly a Roman temple. The gabled façade is adorned with an elegant rounded polystyle portal, with foliated capitals in marble.
The interior, with a single nave, was completely renovated in the 18th century; you can admire paintings by Dono Doni and Ascensidonio Spacca. A small door on the right leads to an inner chapel with frescoes dating back to the 16th century. Next to the altar, in a chapel, there is a stone on which San Francesco placed his feet when he preached to the birds in Pian d’Arca. The second chapel on the right, perhaps a work by Galeazzo Alessi, preserves a beautiful 15th century tabernacle; the small dome is adorned with glazed earthenware attributed to Santi Buglioni.