The Church of San Biagio is located in Plebiscito Square, formerly known as Queen’s Square, a very popular place and in connection with the main streets of the city.
The present church is the result of the reconstruction ordered by Cardinal Filippo Gezza De Rufinis (1356-1380), who had the existing Dominican convent expanded around the 12th-century Romanesque church, with its entrance facing the Aniene River on Via dei Sosii.
The church was flanked by a tall bell tower, destroyed by bombing in 1944.
Tradition has it that an ancient temple dedicated to Juno Regina, adjoining that of Diana, stood in this area, justifying the toponymy of Queen’s Square.
Work on the reconstruction of the church and convent, originally named Santa Maria De Gloria and then San Biagio by the Tiburtini themselves, was encouraged under the pontificate of Boniface IX (1389-1404) and only completed in the 16th century at the behest of Vincenzo Leonini (brother of the Bishop of Tivoli Angelo Leonini).
The church today retains its beautiful tufa facade with an entrance on Piazza del Plebiscito, in which the portal with the Leonini family coats of arms at the bottom stands out; a marble high relief of the Madonna and Child can be seen in the tympanum.
The upper part is adorned with a central rose window located between a Roman clock and a sundial.
The interior of the church has a single nave characterized by a high altar, side chapels, and large windows visible in the chancel.
Works preserved inside the chapels include the 18th-century painting of “St. Catherine of Alexandria,” the painting of the “Most Holy Name of Jesus,” and the Baptismal Font.
Also noteworthy are the frescoes depicting the “Glory of St. Thomas Aquinas” and the “Madonna in Glory” holding the baby Jesus located near the sacristy.
In the chancel is the beautiful fresco of the Crucifixion, dating from the second half of the 1200s. Of the Dominican cloister only the four round arches resting on the frescoed pillars remain visible.
In the inner courtyard of the present church is the Lapidary Museum of the Cloister of St. Blaise where it is possible to observe tombstones, usually from the same church, important for the history of Tiburtine families, whose names are recalled (Domenico Zappi, frà Lorenzo Petrarca, Giovanni de Cors bishop of Tivoli, Clemente Brigante Colonna, Alfonso Colonna, Stanislao Viola…).
