The patron of Santo Stefano di Magra is Saint Stephen the Protomartyr, celebrated on 3 August. The pieve dedicated to him is mentioned in a document by Pope Anastasius IV from 1154; as early as 981, in the imperial diploma of Otto II of Saxony, the town was recorded as an important market site along the Via Francigena, the road of pilgrims bound for Rome. The present parish church, in the old town centre, was built during the 18th century on that ancient 14th-century pieve: designed by the Genoese architect Ferdinando d'Andrea, it opened for worship in 1764.
In the hamlet of Ponzano Magra stands instead the sanctuary of Nostra Signora delle Grazie, built following a Marian apparition to the boy Giovanni Battistini, which tradition places on 10 July 1647 on the Castiglioni hill: the first stone was blessed by the bishop on 24 August 1648, and inside it still holds and displays a Madonna and Child by Domenico Beccafumi.
