6Masada – Israel (circa 30 BC)

Masada is not a castle in the traditional European sense, but this desert fortress overlooking the Dead Sea deserves its place on the list.
Constructed by Herod the Great in the 1st century BC, it was later the site of a dramatic siege by Roman forces. With its cliffside location and elaborate system of palaces, baths, and storerooms, Masada reflects both architectural brilliance and tragic history.