The parish church stands in the XI Febbraio square, near the baptistery, overlooking the renowned Venere Gulf, from where you are presented with an enchanting view. The church was built in the 5th or 6th century on the ruins of a watering place, dating back to the first century, but the building that can be seen today is the result of the restoration works of the 16th century. Originally the church had just one nave and lateral arcades, but in the 16th century it was transformed into a three naves church. The façade, finished in 1698, is an example of mannerism and baroque style. Inside the church, worth seeing are also the trapezoidal crypt, with five bays and three apses, the 16th-century altar-piece representing the martyrdom of S. Stefano and the lateral chapels, decorated with interesting 17th-century frescoes and stuccoes.