The patron saint of Borzonasca is Saint Bartholomew, celebrated on 24 August. The parish church dedicated to him is also the sanctuary of the Holy Crucifix: venerated in the niche of the high altar is a crucifix that, according to tradition, was brought from the East following a crusade. The parish community was under the diocese of Piacenza-Bobbio until 1989.
In the hamlet of Borzone stands the abbey of Sant'Andrea, founded, according to tradition, in 714 and rebuilt in Gothic-Romanesque forms in the 12th century: declared a national monument in 1910, it is considered one of the finest religious monuments of the Sturla valley. Not far away is a rock carving among the largest in Italy and Europe, possibly dating from the Paleolithic, which legend says the abbey's monks visited once a year.
