Castel del Monte

Castel del Monte is one of the most mathematically extraordinary buildings of the Middle Ages: a perfect octagonal castle with eight octagonal towers, built by Holy Roman Emperor Frederick II around 1240 on a hill above the Apulian plain in Puglia. Every element of the design is based on the octagon — the plan of the castle, the plan of each tower, the plan of the courtyard — and the proportions throughout suggest a deliberate programme of geometric and perhaps astronomical symbolism that has never been fully decoded.

Frederick II was himself an extraordinary figure — polyglot, scientist, patron of Arab and Jewish scholars, author of a treatise on falconry, and simultaneously Holy Roman Emperor, King of Sicily and King of Jerusalem. His building at Castel del Monte reflects interests that went far beyond military necessity: the castle was certainly not intended as a serious fortification (it has no moat, drawbridge or defensive outworks). Whether it was a hunting lodge, a monument to Frederick's cosmological beliefs, an astronomical instrument or something else entirely remains debated by scholars.

The castle appears on the Italian 1-cent euro coin, making it one of the most reproduced images in Europe. The interior, while largely empty of furnishings, retains Gothic windows of great delicacy, marble columns, and carved details of exceptional quality. The view from the castle's position — 540 metres above the Apulian plain, alone on its hill — encompasses an enormous sweep of the Murge plateau.