The patron saint of San Lorenzo al Mare is Saint Mary Magdalene, celebrated on 22 July, in the parish church dedicated to her in the main town, dating from between the 13th and 14th centuries and remodelled in Baroque style during 1766, which houses several cycles of frescoes by anonymous painters.
The town's name, though different from that of its patron saint, comes from the San Lorenzo stream, along whose banks today's settlement extends, divided between the coastal and hillside areas into two urban clusters that, seen from above, recall the shape of an anchor: it was the town of Porto Maurizio that decided to build a new urban settlement on the left bank of the San Lorenzo stream, after the Lengueglia, the local lords, had ceded the feudal territory of Pietrabruna to Porto Maurizio itself.
