Trapani Cathedral, otherwise the Basilica of St. Lawrence the Martyr (Italian: Duomo di Trapani; Basilica cattedrale di San Lorenzo martire) is the cathedral of the Roman Catholic Diocese of Trapani, dedicated to Saint Lawrence. It is located in Trapani, Sicily, Italy. The church was built by order of Alfonso the Magnanimous in 1421 and was elevated to a parish in the second half of the fifteenth century. In 1844, when the Diocese of Trapani was created, the church was made its episcopal seat. Over the following centuries, the building was modified several times and its current appearance dates from the restoration of the eighteenth century by the architect Giovanni Biagio Amico.