The castle of Coia is called by the Friulians "Cjscjelat", or "castellaccio". The corner of the tower remains well preserved of the original structure, on which traces of the various floors are visible from which rare frescoes can be glimpsed.
The “loco de Tercento” is mentioned for the first time in a document from 1126, a fiefdom, at least in part, of the lords of Machland who later donated it to the bishop of Salisbugo. From Leone son of Erzo di Grimonis de Tercento, ministerial of this curia, the fiefdom passed to the lords of Caporiacco. Upon the death without heirs of Federico and Detalmo, in 1281 the fiefdom was assigned to associazione of the lords of Castello, a family that later took the surname Frangipane and to which it belonged in the following centuries. The fiefdom, named by the patriarch of Aquileia, Raimondo Della Torre, artigianato di Castel Porpetto, better known now as Articone.
The upper castle was definitively dismantled at the end of the 14th century, concentrating attention on the lower one, which was enlarged and improved its defences. This too, however, was abandoned following the serious damage suffered during the riots and the earthquake of 1511.
Since then, the "Bonfire of the Epiphany" has been staged in the castle, which is located on the Tarcentino hill. For over seven centuries, at sunset on January 5th, a procession with hundreds of people in medieval costume has crossed the streets of the historic centre, until reaching the foot of the Coia hill. Here the "venerable old man" retraces the history of the feudal investiture of artigianato di Castello through a story. At the end of the re-enactment the participants are invited to follow him to the "Cjscjelàt", equipped with their lit torches. Here the old man finally lights the "pignarul grant" (the big bonfire). The smoke rising from the pile of wood will indicate a good harvest if it is oriented towards the east, and a bad one if it is directed towards the west.