Dictionary of Greek and Roman Geography/Turris Libyssonis
TURRIS LIBYSSONIS (Πύργος Λιβύσσωνος, Ptol.: Porto Torres), a town of Sardinia, and apparently one of the most considerable in the island. It is situated on the N. coast about 15 miles E. of the Gorditanian promontory (the Capo del Falcone), and on the spacious bay now called Golfo dell' Asinara. Pliny tells us it was a Roman colony, and we may probably infer from its name that there was previously no town on the spot, but merely a fort or castellum. (Plin. iii. 12. s. 17.) It is noticed also by Ptolemy and in the Itineraries, but without any indication that it was a place of any importance. (Ptol. iii. 3. §5; Itin. Ant. p. 83.) But the ancient remains still existing prove that it must have been a considerable town under the Roman Empire; and we learn from the inscriptions on ancient milestones that the principal road through the island ran directly from Caralis to Turris, a sufficient proof that the latter was a place much frequented. It was also an episcopal see during the early part of the middle ages. The existing port at Porto Torres, which is almost wholly artificial, is based in great part on Roman foundations; and there exist also the remains of a temple (which, as we learn from an inscription, was dedicated to Fortune, and restored in the reign of Philip), of thermae, of a basilica and an aqueduct, as well as a bridge over the adjoining small river, still called the Fiume Turritano. The ancient city continued to be inhabited till the 11th century, when the greater part of the population migrated to Sassari, about 10 miles inland, and situated on a hill. This is still the second city of the island. (De la Marmora, Voy. en Sardaigne, vol. ii. pp. 363, 468-472; Smyth's Sardinia, pp. 263-266.)