The castle of Vianden, the imposing home of the counts, was not only a medieval fortress in which comfort was sacrificed to defensive demands, but also a real palace (Henri-Paul Eydoux).
In Carolingian times, the castle was originally a decagonal tower, later transformed into a chapel. This chapel, the " Little Palace" and the "Great Palace" - the most beautiful parts of the castle - were erected in the first half of the 13th century. The Juliers Quarter, on the west side of the Great Palace, dates from the beginning of the 14th century, whereas the Nassau Quarter was only built at the beginning of the 17th century.