The Castello Maniace is a citadel and castle in Syracuse, Sicily, southern Italy.
It is situated at the far point of the Ortygia island promontory, where it was constructed between 1232 and 1240 by the Emperor Frederick II.
Today the castle is open to the public and is a local tourist attraction in Syracuse.
The first fort was built here in 1038 by George Maniakes, a Greek general and later the Catepan of Italy, after he captured Syracuse from the Arabs on behalf of the Emperor Michael IV.
Frederick II, as King of Sicily, had his architect Riccardo da Lentini build it in 1232–1240.