Castel di Sangro is a city and comune of 6,461 people in the Province of L'Aquila, in Abruzzo, central Italy. It is the main city of the Alto Sangro e Altopiano delle Cinque Miglia area.

The province of L'Aquila is the largest, most mountainous and least densely populated province of the Abruzzo region of Italy. It comprises about half the landmass of Abruzzo and occupies the western part of the region. It has borders with the provinces of Teramo to the north, Pescara and Chieti to the east, Isernia to the south and Frosinone, Rome and Rieti to the west. Its capital is the city of L'Aquila.