San Gregorio is the Mother Church of Vizzini and therefore the major religious building in town. It is built in a variety of styles and has a beautiful 15th Century Gothic-Catalan portal which is the only part to survive the earthquake of 1693. It has an octagonal plan which is divided into three naves with ogival arches and a wooden ceiling that was designed by one of the Bonaiuto family. The interior also has some good artworks such as two paintings by Filippo Paladini which date from the early 17th Century depicting the Martyrdom of San Lorenzo and the Madonna della Mercede.