The patron saint of Rosolini is Saint Aloysius Gonzaga, celebrated on the first Sunday of August. His relic, a jawbone, is kept in the Mother Church of San Giuseppe, built between the 18th and 19th centuries.
The origins of the territory of Rosolini are tied to the history of the ancient Val di Noto: for centuries the area, inhabited since prehistory as attested by the many archaeological sites in the surrounding quarries and plateaus, remained without a true stable urban centre, taking shape as a set of agricultural fiefs administratively dependent on the city of Noto. The fief complex included, besides the princes' residence, warehouses, stables, armouries, the offices of the feudal government and the church of the Immaculate Conception, originally dedicated to Saint Jerome; around this core the settlers' dwellings and the new community's main civic and religious functions progressively developed. Among the town's other religious traditions are the feast of Saint Joseph, celebrated on the first Sunday after 19 March with a votive cavalcade, and the Good Friday procession with the Holy Thorn, the Christ at the Column, the Cataletto and the Sorrowful Mother.
