Olbia is a city and commune of 60,346 inhabitants (May 2018) in the Italian insular province of Sassari in northeastern Sardinia, Italy, in the historical region of Gallura. Called Olbia in the Roman age, Civita in the Middle Ages (Judicates period) and the Terranova Pausania until the 1940s, Olbia has again been the official name of the city since the fascist period.