From their ancestral seat, located on a rock high above the Adriatic Sea, they controlled the trade routes running from the city of Monfalcone along the coast to the Istrian peninsula.

Serving as ministeriales of the Counts of Gorizia and also of their successors, the Habsburg archdukes of Inner Austria, they secured their position in the Friuli region.

Below the ruins of the ancient castle there lies a white rock projecting into the sea, the Dama Bianca, which resembles a veiled woman and gave origin to many gothic legends.

By the late 19th century, Duino with its scenic views and Mediterranean climate had become a fashionable seaside resort on the Austrian Riviera.

[4] During the years of the Free Territory of Trieste (1947–1954), however, its ethnic composition changed considerably, as many Istrian Italians fleeing from Yugoslavia settled in Duino.