The town of Tricesimo, in its name, recalls a Roman settlement built 30 miles (Tricesimum or Tricensimum) from Aquileia, mentioned in the Itinerarium Antonini Augusti of the third century AD but probably already existing a few centuries earlier to control the important consular road towards Noricum. The castle is documented starting from the 13th century, subject to the lords of the same name; by the end of the century, however, it was already of direct patriarchal relevance. With the advent of the Venetian Republic, the fortress was governed by a captain and then passed into the ownership of various families. From the lords of Montegnacco, who had held it for over a century, in 1627 it passed to the noble Valentinis, with whom it remained until 1948, the year in which it was sold to the Catholic Action of Udine. Over the centuries, the castle was the subject of numerous renovations and expansions; Worthy of note are those commissioned by the Prampero and Montegnacco families, who painted the fresco by Pomponio Amalteo in the chapel, and above all those carried out in the seventeenth century and in the last century by the Valentinis family, who brought the manor to the appearance it still retains.