Located in Apulia, Italy, Castel del Monte is a perfect example of symmetry in medieval architecture. It was built by Frederick II, the Holy Roman Emperor and its construction which began in 1230, took ten years to complete. The name literally means "Castle of the Hill" and with a reason: It was built on a hill providing it with an excellent strategical position.
The castle was mainly used by Frederick as a hunting lodge until his death in 1250. Shortly after his death, it became a prison until it finally fell into disrepair during the hard times of the Holy Roman Empire. The main wall is 25 meters tall and very thick. Even though the columns were made of marble, most of them were stolen by vandals and today none remain.
The castle was finally purchased in 1876 by the Italian government which began restoration 40 years later.