The vines from which Prosecco is produced must grow exclusively to the area of North East Italy lying between Dolomites and the Adriatic Sea. The grapes come from five provinces in the Veneto region (Belluno, Padua, Treviso, Venice, Vicenza) and four provinces in Friuli Venezia Giulia (Gorizia, Pordenone, Trieste and Udine). When the wine is also produced and bottled exclusively in the provinces of Treviso and Trieste, a special mention may be written on the label in recognition of the invaluable part these two provinces have played in the history of Prosecco.