According to a legend, it was built by Emperor Constantine after the Edict of Milan. The local tradition attributes the building of the church to Pope Simplicius, who was born at Tivoli. The Liber pontificalis, in the biography of Pope Leo III, contains the first reference to the "basilica beati martyris Laurentii sita infra civitatem Tyburtinam". Whatever the exact date, the first church was built over the basilica in the forum of the Romancity ofTibur, whose apse can still be seen behind the one of the present building. This church was rebuilt in Romanesque style between the 11th and 12th centuries, and the bell tower belongs to this rebuilding. The present cathedral, in Baroque style, was built by order of Cardinal Giulio Roma, bishop of Tivoli from 1634 to 1652. It has one nave with side chapels. It was consecrated on February 1, 1641, and completed with the portico in 1650. In 1747 the side door on the north was created, while the inside decoration dates from the early 19th century.
Description
The west front of the church has a portico with three arches, and is flanked by the Romanesque bell tower, about 47 meters high. The interior was decorated by the Roman painter Angelo De Angelis in 1816: on the vault are paintings depicting The Glory of St. Lawrence, Faith and Religion, while in the apse are depicted four saints from Tivoli: Pope Simplicius and the martyrs Generosus, Symphorosa and Getulius. The altarpiece represents St Lawrence in front of the Judge, and was painted by Pietro Labruzzi.
Side chapels
Four chapels open along the south side of the cathedral:
Chapel of the Most Holy Savior: decorated by Vincenzo Manenti. Over the altar is the renowned Triptych of the Savior, a work by the Benedictine monks of Farfa Abbey. The silver cuirass from the triptych, made by Tuscan craftsmen in 1449, is now preserved in a showcase on the left
Chapel of the Persian Martyrs: decorated by Bartolomeo Colombo, an assistant of the famous painter and architect Pietro da Cortona. This chapel is located in the passage to the side door of the church. On the right is the funerary monument of the Tiburtine bishop Angelo Leonini, who died in 1517
Also on the north side, the sacristy was designed by architect Giovanni Antonio De Rossi, and contains frescoes by Giovanni Francesco Grimaldi, and oils on canvas by Innocenzo Tacconi, with The Martyrdom of St Lawrence, and Vincenzo Manenti, with portraits of Cardinals Roma and Santacroce.