The Castle of Pazin is the biggest and the best-preserved medieval fortress in Istria, Croatia. Originally built around late tenth century it was ravaged and rebuilt several times. From 14th century onwards it was owned by Austrian house of Habsburgs. Presently it houses the Ethnographic Museum of Istria and the City Museum of Pazin.
The Castle and nearby gorge inspired Jules Verne for the novel "Mathias Sandorf" (1885). One of the street which leads to the castle is now named after Jules Verne.
More info: Wikipedia and Archaeological Sites of Adriatic Sea.