Palace of the Grand Dukes of Lithuania
The Palace of the Grand Dukes of Lithuania (Lithuanian: Lietuvos Didžiosios Kunigaikštystės valdovų rūmai Vilniaus žemutinėje pilyje; Polish: Zamek Dolny w Wilnie) is a palace in Vilnius, Lithuania. It was originally constructed in the 15th century for the rulers of the Grand Duchy of Lithuania and the future Kings of Poland.
Source: Wikipedia — Palace of the Grand Dukes of Lithuania (CC BY-SA 4.0)