Its structure is originally a Greek doric temple, and for this reason it is included in a UNESCO World Heritage Site designated in 2005.

[2] Archeological site excavations by Paolo Orsi in 1907-1910 show the Greek temple to have been built on even older foundations, and uncovered a wealth of archaic and pre-Hellenic artefacts.

As part of the increased building activity after the 1693 Sicily earthquake, the cathedral was rebuilt and the façade redesigned by architect Andrea Palma in 1725–1753.

[5] Twice a year on the first Sunday in May and on December 13, her feast day, a statue of Saint Lucy by sculptor Pietro Rizzo (1599) is brought out of the cathedral and paraded through the streets.

The cathedral shares the Piazza Duomo with the Church of Santa Lucia alla Badia, a short walk to the south.

This programme aims to catalogue, name and conserve sites of outstanding cultural or natural importance to the common heritage of humanity.