Holy Roman Emperor Frederick II of Hohenstaufen built Castel del Monte on a hill outside the present-day Italian town of Andria, in the Puglia (Apulia, in English) region. Although the castle dates back to around 1240 A. D., no one knows exactly why it was built the way it was, or why Frederick chose that location.
Castel del Monte was not built for defensive purposes, apparently. It was, however, oriented to the signs of the zodiac and to the sun, and its main doorway was designed to correspond to one of the most famous mathematical ratios of all time. Even Dan Brown couldn't invent a more fascinating medieval castle.
Take our photo tour of Castel del Monte, now a UNESCO World Heritage Site, and learn more about Holy Roman Emperor Frederick II and his unique castle.
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Photo © Steve Parode