According to tradition, this oratory was built over the tomb of Saint Eufrosino, who lived here and died, probably in the 7th or 8th century A.D. Although he is considered the evangelizer of Chianti, he did not preach in the Apostolic Age but at a later time, when missionaries were sent from Rome to Tuscany by the Lombard authorities.
The oratory was mentioned in a bull by Pope Paschal II as early as 1102. Its Romanesque origins are clearly indicated by some structures encapsulated in the façade and the right wall of the church. The oratory we see today, however, dates from the mid-15th century, when Pope Eugene issued a bull granting indulgence to the church, as it preserved the relics of the saint.
The church has a rectangular plan with a single nave ending in a square apse; the trussed roof rests on the outside on a cornice of carved sponge stone. The façade is embellished by a pietra serena portal, probably coeval with the portico on the left side of the church, dating from the late 16th century.
Inside the church are two altars with a reliquary statue of Saint Eufrosino dating from the 18th century. In the apse is a large aedicule where the relics of the saint were once displayed.
Due to the age-old scarcity of water typical of the Chianti countryside, this place with its spring was deeply venerated, as shown by a small chapel behind the oratory. It contains a stone altar from the 12th century, decorated with interesting bas-reliefs. A hole opens in its base, through which the spring water must have been visible in the past.