THE BAPTISTERY AND DUOMO

The Baptistery of St. Giovanni is from the period shortly before that of the romanesque Duomo. At that time, italian baptisteries were usually round or octagonal in plan. It is assumed, therefore, that the Baptistery of St. Giovanni had originally been a church, since it is rectangular in plan.
Several pieces from Roman times are to be found on its external walls: these had been recovered from demolished Roman buildings and incorporated into the walls, as was the custom.
Between the Baptistery and Campanile stands the Scuola del Santissimo, on whose facade one can still make out a Crucifixion by Titian.
Internally, the Baptistery is very sober and linear, with Bizantine frescoes and on the main altar a "Baptism of Christ" by Ascanio Spineda.
The site  where the Duomo now stands is thought to have been a seat of Cristianity during the first half of the 4th century. The mosaic pavement of a paleochristian baptistery, still visible today in via Canoniche, appears to support this claim.
The site then seems to have been host to a church of the Longobard era, evidence of which is found in several architectural elements used in the construction of the existing crypt. This cript, built around the early 11th century, is supported by many re-used columns and capitals, all different from one another.
Over this, possibly, Longobard church, the romanesque basilica was built in the first half of the 12th century. Unfortunately, only the external part facing via Canoniche and Piazza Pola remains. In 1750 due to its state of decay, a competition was announced for the Cathedral's renovation, resulting in its almost total demolition and recladding. The proposal by Giordano Riccati gives us the Cathedral as we know it today, though due to economic reasons, the demolition of the rear section towards via Canoniche and Piazza Pola did not eventuate, happily leaving us a feel of the old medieval times.
The 16th century chapels to the side of the Duomo's main altar were also saved from the complete demolition of the romanesque cathedral. These are the Cappella del Santissimo Sacramento, by Antonio Lombardo with sculptures by Bregno; and the Cappella dell'Annunziata or Cappella Malchiostro, named after he who commissioned it. The altarpiece of this last Cappella is by Titian and represents the Annunciation: on the walls are frescoes by Pordenone and along the vestibule, the "Madonna del Fiore" (1487) by Girolamo da Treviso il Vecchio, the "Adorazione dei Magi" (Adoration of the Wise men), 1550-1560, and St. Lorenzo (1562) both by Paris Bordone.
The sacristy also has a painting by Bordone representing "I Sacri Misteri" (1551), and a painting of the "Processione in Piazza Duomo" (procession in Piazza Duomo) (1571) by Francesco Dominici: a very important historical document for the city, with its clear and meticulous description of Piazza Duomo as it was in the second half of the 16th century. There are also other valuable works of art in the Church: a statue representing St.Sebastiano (16th century) by Lorenzo Bregno; a painting by Francesco Bissolo of "Santa Giustina tra Santi e donatore" (circa 1530); a statue from the studio of Sansovino reproducing the "Madonna con bambino" and a fresco of the "Redentore" (1511) by Pier Maria Pennacchi.

SAN NICOLO' (ST. NICHOLAS)

Construction of the church began towards the end of the 13th century but, due to lack of funds and the interuption of war, lasted for more than two centuries. Its completion is greatly due to the Dominican cardinal Nicolò Bocassino, after whom it was named, later to be Pope Benedetto XI, who gave over 70,000 gold fiorins for the construction of the church to continue. Construction was completed in 1858, post-French occupation.
The church of St. Nicolò was built in the very severe romanesque gothic style. It is a very imposing structure, the biggest in Treviso, and one of the tallest of its contemporaries in Italy. Internally, it has a Latin cross plan, with five apsidal chapels, a celling in the shape of a ship's hull and twelve huge pilasters which support the entire structure. These last symbolise the twelve apostles who sustain the church of th faithful: one of these has a fresco by the great artist, Tomaso da Modena and represents, in this typical style and technique, the images of the saints Romualdo, Girolamo, Giovanni Battista and Agnese.