Penmarc'h has 4 chapels.
The small chapel of Saint-Pierre, located between the Semaphore and the Old Lighthouse, hosts seasonal exhibitions.
This building dates from the end of the 14th century. The chapel is dominated by an imposing fortress-like tower. It was halved around 1835, when the old Penmarc'h lighthouse was built. Solidly built, it defended the port of Saint-Pierre. Its fire tower served as a semaphore-mirador to warn of the arrival of pirates and other Englishmen. The chapel was restored in 1843 and the roof redone in 1930.
There is an entrance at the bottom of the tower, and another in an embrasure giving direct access to the chapel. Note the small four-lobed bay to the east of the door.