Castel del Monte is a medieval and Renaissance hill town and comune in the province of L'Aquila in northern Abruzzo, Italy. Located in the heart of the Gran Sasso mountain range, the town is set into a steep hillside nestled beneath mountain peaks near the high plain of Campo Imperatore. Castel del Monte sits opposite the ancient mountaintop fortress of Rocca Calascio and faces Monte Sirente in the distance. It is located in the Gran Sasso e Monti della Laga National Park.