An old belief states that in this Norman church, commissioned by Roberto Guiscardo in 1072, the future mother of Frederick II Queen Constantine D’Altavilla and Santa Rosalia, patron saint of the city before retiring to hermetic life, became nuns. With the aim of creating an even more sumptuous temple overlooking the Cassaro, the church was demolished and rebuilt, first in 1528 and later in 1682 by Paolo Amato, who made the two larger chapels and projected the elliptic dome. Partially destroyed by bombings in 1943 and restored in 1959, it houses stuccos, decorations and majestic frescoes by Vito D’Anna. Today it is used as an auditorium for classical concerts.