Four great imperial roads were built in Sardinia during Roman times (fig. 1): the first, a portu Tibulas-Caralis, linked Cagliari with the area of Santa Teresa of Gallura, along the east coast; another started from Carales and ran along the western coast, connecting Nura, Sulcis, up to Turris Libisonis (which corresponds to today’s Porto Torres), ending in Tibula itself (fig. 2); the third road, corresponding roughly to today’s State Road 131 "Carlo Felice", connected Carales with Turris Libisonis; the last one, still starting from Carales, ran through the hinterland, passing close to the Gennargentu massif, and ended at Ulbia (fig. 3).

Fig. 1 - Sardinian roads during Roman Imperial Times (from MASTINO 2005, fig. 37).

Fig. 2 - North Sardinian roads during Roman Imperial Times
(from MASTINO 2005, fig. 37).

One of the imperial roads built in Roman times, a portu Tibula-Caralis, ran along the east coast and passed close to Posada. From this area a diverticulum (side road) branched off which connected Portus Luguidonis with the innermost settlement of Caput Tyrsi, in the territory of Buddusò (fig. 4). When the Roman Empire fell, it is quite likely that this important internal road maintained its economic importance, as later settlements such as Sulla, Arischion and Posada were successively built along it.

Fig. 3 - The region of the Posada Barony during Roman Imperial Times (from BONELLO, MASTINO 1994, fig. 1).

Fig. 4 - Diverticulum of a Portu Tibulas - Caralis, which connected Portus Luguidonis to Caput Tyrsi (from BONELLO, MASTINO 1994, fig. 1).