It is part of the convent complex of St. Agostino. The foundation dates back to the constitution of Pietrasanta in 1225. From the era it conserves part of the left transept that is still clearly identifiable in the ensemble of the wall structure of the XVI century, year of the reconstruction during the domination of Castruccio Castracani. Still noteworthy is the 14th-century building installation, with the imposing and austere three-sectioned façade, embellished by the architecture on the top and by the prestigious bas-reliefs that take the form of the pointed arch, placed as a crown on the trabeations of the entrances and representing the coat-of-arms of Pietrasanta and the dominations of Genoa and Florence.
Right on the architrave of the side door you can see the date 1330, indicating the construction of the façade. Also richly decorated is the marble rose-window that sits well in the white façade. The octagonal dome, between the transept and the main nave dates back to the second half of the 1400s, reworked in the 17th century during the importance restoration works requested by the Grand Duchess Madama Cristina di Lorena, just like the internal furnishings and the boring along the sides.
On the iridescent marble aspect of the Church the high bell tower imposes itself in red bricks, started at the end of the XV century and never finished. The bare aspect owing to the lack of marble covering should not deceive however, as it hides a real masterpiece: the extraordinary helicoidal staircase that runs vertically inside it.
Source: Versilia Tourist Information Office