Until the middle of the nineteenth century, was composed of one nave with four small lateral chapels (that of Jesus Christ, charity, Purgatory and Sant'Antonio) and various altars, which if it contarono 7 already in 1544. In 1870, the archpriest don Michele Arcangelo Volini did expand further the central nave, restructured the sacristy, journeyed back the campanile and gave shape to the two side aisles. At the beginning of the Twentieth Century, the church was adorned with various altars in marble, thanks to the contribution of US emigrants from Castelmezzano. The building retains works as the statues of "Santa Maria dell'Olmo", the "Madonna with Child", the "Madonna of pure Bosco-Regina" and the "Madonna of the Ascension". There are three paintings enrich the interior: that of "purgative souls", the "Madonna del Carmelo", of "Holy Family" (or "Trinity Terrestrial"), attributed to the seventeenth century painter Pietrafesa. To mention also the bells of the Church: the oldest dates back to 1666, the second to 1768, the third to 1820, and the fourth to 1948.