The Complesso Monumentale di San Costanzo al Monte is located in the woods of Mount San Bernardo, scene of the martyrdom of San Costanzo, between 303 and 305 A.D. The magnificent church dates back to 1190 and is considered a masterpiece of architecture and a monument of considerable importance for the religious and artistic history of Piedmont. The cult of San Costanzo is celebrated here because he is the patron saint of the ancient diocese of Saluzzo along with San Chiaffredo.

The ancient Romanesque-Gothic church was extended and reworked in later periods until the eighteenth century, when the façade was created. The ancient bell tower has survived, as have the three semicircular apses adorned externally with Lombard bands dating back to the 12th century. 

Inside, the upper floor of the church leans on the lower crypt that preserves the ancient stone vaults. Parts of a Romanesque section are all that remains of the original frescoes that decorated the three upper naves.