Archaeological excavations have revealed human presence in the Castelsardo area since pre-Nuragic and Nuragic times, as well as during the Roman period in Sardinia. After the fall of the
Western Roman Empire, the monastery of
Nostra Signora di Tergu was founded nearby, but the current town originates from the castle built here, in 1102 (or 1270), by the
Doria family of
Genoa. The castle and the village, which gradually formed around it, were the seat of the Doria's fiefdom on the island called Castel Doria or Castelgenovese. It was conquered by the Aragonese in the 15th century (1448) and renamedCastillo Aragonés (Castel Aragonese). Except for the
Maddalena archipelago, it was the last city on the island to join the
Kingdom of Sardinia. Castelsardo was part of the
Savoy's
Kingdom of Sardinia, obtained by the will of King
Charles Emmanuel III. ==Main sights==