The remains of the Castle can be visited
Dvigrad Castle

The Dvigrad castle ruin, a former settlement now known as a deserted town, is on a hill in the Draga Valley on the Croatian peninsula of Istria.
History+
Dvigrad's origins date back to prehistoric times when Illyrians settled the area. In 1345, the settlement was plundered by Genoese Admiral Paganin Doria during a conflict between Genoa and Venice. Only a few years later, in 1383, Dvigrad suffered another looting, this time by Venetian troops. It was not until 1413 that the Venetians appointed a nobleman from Koper as governor. In the 16th century, the site was afflicted by severe epidemics such as the plague and malaria, leading to a population decline.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: Dinko Gubic
This description draws on the facts documented in the linked Wikipedia article; Wikipedia content is licensed under CC BY-SA 4.0. Wording and editing: Mobile History.
Location: 45.1270, 13.8118