St. Anthony's Chapel built in the 16th century and rebuilt after an earthquake between 1675 - 78, has an octagonal shape, is surrounded by columns and is faced with marble.

It was erected in memory of the miracle of the mule, performed by the Saint on this site, around 1227.
It is said, that the miracle of the mule occurred through the intercession of Saint Anthony of Padua in Piazza Tre Martiri in Rimini. According to the tradition, the saint was handing the consecrated host to the citizens when a farmer passed by in company of a mule, who had been fasting for several days.  The mule, having refused the fodder and hay that had been put in front of her, prostrated herself before the hand of the saint who was holding the consecrated host.