CITTANOVA of the ESTUARY. — It is one of the smallest cities founded, according to Venetian traditions, when the inhabitants of Opitergium were forced to seek refuge in the lagoons under Longobard pressure. It was also called Eraclea. It cannot be determined when it became an episcopal see, but certainly in the 9th century it was subject to the metropolitan see of Grado. In 1440 it was incorporated into the diocese of Grado.
BIBL.: P. Paschini, I vescovi di Cittanova d'Istria e di C. dell'E. durante il grande sisma, in Atti e Memorie della Società istriana di archeol., ecc., 44 (1932); V. PAVIA, Il patriarcato di Venezia, ecc., Venezia 1938, p. 120 SEG.; P. Paschini, Le origini della diocesi di Ceneda, in Miscellanea Mercati, V. Città del Vaticano 1946, pp. 145-59.