Erected in 1096 by Bishop Gerlando, and probably the remains of a temple attributed to Zeus Atabirio, it stretches for almost 100 meters in length and 40 in width. The interior is divided into three main aisles separated by two rows of massive pillars ending in pointed arches. The ceiling of the nave is divided into two parts: the first dating back to around 1518 with uncovered beams with masterfully decorated wooden trusses, and the second in 1682, gilded with a central large-headed eagle.

There are beautiful immense arches and its core richly adorned with gilded stucco. There are numerous works of art in the church. Among the most notable are the ark of silver made in 1639 containing the relics of San Gerlando, the beautiful marble statue of the Madonna and Child (XVI sec.), attributed to the school of Gaggini, and the frescoes and canvases adorning the entire temple. In the right glass alcove, there is an urn that contains the embalmed glass that tradition attributes to the Brandimarte, fallen on the beach of Lampedusa in the clash of the "three on three" described in l'Orlando Furioso.