The city lies at the base of a deep ria on the northeastern coast of Sardinia and extends across a stretch of plain on the shore of the gulf of the same name. The city has one of the island's most important commercial and tourist ports and an airport, the "Costa Smeralda," considered one of the most important in Italy.
The city developed on a stretch of coast favorable from a geographical and environmental perspective, both for its function as a natural coastal outlet for inland areas and for the importance of the port on the commercial and military maritime routes of the central Tyrrhenian Sea.
Recently, thanks to new excavations and studies, it has been possible to delineate the stages of urban evolution. From the second half of the 8th to the first half of the 7th century BC, the existence of a Phoenician warehouse or colonial settlement is attested (Phoenician materials with some rare imitations of Euboean materials); but from the mid-7th to the mid-late 6th century BC, the presence of a Phoenician warehouse or colonial settlement is attested. Only material of Greek origin has been found (Corinthian artefacts and, from the late 7th century, Ionian artefacts). This evidence would prove the existence of a Greek "colony" that replaced the previous Phoenician settlement and existed for at least a century and a half.
From the second half of the 6th century BC, the situation appears to have changed. Indeed, the Battle of the Sardinian Sea in 540 BC, which pitted the Carthaginians and Etruscans against the Greeks, almost certainly also affected Olbia. The victory secured the Etruscans and Carthaginians' domination of the central Tyrrhenian Sea, depriving the city of its natural trade routes and creating a situation that led to the Carthaginian conquest of the city, thereby securing control of the central Tyrrhenian area. Later, around the mid-4th century BC, the Carthaginians organized an urban center defended by a trapezoidal wall with square towers and bordered to the west by the necropolis that extended beyond the western perimeter of the walls, beyond the current Via Brigata Sassari.
Due to its strategic role, the city was involved in the events of the First Punic War. In 259 BC, the Roman consul Lucius Cornelius Scipio attempted, unsuccessfully, to free it from Carthaginian rule. However, later, in 238-237 BC, the whole of Sardinia, including Olbia, came under Roman rule. The city remained under Roman rule for a long time, until the founding of Turris Libisonis, the main city of northern Sardinia. The Roman city occupied the previous Punic settlement within the same defensive circuit, using the still-functioning structures and infrastructure, such as the orthogonal urban plan whose road network appears to have been oriented along north-northwest-south, southeast, and west-northwest-east-southeast axes (the main roads perhaps corresponded to the current Corso Umberto and Via Regina Elena-Via Porto Romano); the port located near the current one; and the sanctuary dedicated to Olbia's patron god, Hercules (Melqart-Herakles-Hercules), identified on the relief of San Paolo, in the center of the town, near the present-day church of Santa Croce.
A cult area consisting of an underground cella (favissa), dating to the 3rd-2nd century BC, was discovered in a suburban area, near the present-day church of San Simplicio. It contained figurative terracottas related to the cult of Demeter, goddess of agriculture. The persistence of this cult in the Roman Imperial period is confirmed by the discovery of the epistyle of a small temple dedicated to Ceres (a Roman goddess assimilated to Demeter) by Acte, Nero's freedwoman and concubine. It is assumed that the forum may have been located in the area of ​​the current school building on Corso Umberto, near the port.
During the 2nd and 1st centuries BC, the city imported goods primarily from central and southern Italy, Spain, Sicily, and North Africa, and exported primarily wheat, as evidenced by the presence in Olbia between 57 and 56 BC of Quintus, Cicero's brother, who was responsible for the grain supply. During the Imperial period, the city, now deeply Romanized, continued to be one of the main Mediterranean trading ports. Between the end of the 1st century BC and the beginning of the 1st century AD, the probable temple structure discovered in Piazza Santa Croce, not far from the Sanctuary of Hercules, was built. The discovery of two imperial portraits (Nero and Trajan) nearby could suggest the existence of an imperial place of worship (Augusteum), and it is likely that the city became a municipality during the 1st century AD. Especially starting from the Neronian era (54-68 AD), it underwent an important phase of urban development, perhaps also linked to the presence of Atte and the economic interests deriving from the management of the estates donated to him by Nero and from the production of bricks in his own workshops. The inhabited area (the area of ​​​​present-day Villa Tamponi, Su Cuguttu) was expanded.
Public and private construction activity intensified with the laying of paved streets, the construction of monuments, and stately homes. During the 2nd century AD, the city was equipped with a thermal baths, located between present-day Corso Umberto and Via delle Terme, and an aqueduct. Port facilities were also strengthened with the construction of warehouses. The seabed off the coast of Olbia preserves numerous archaeological sites, further evidence of the port's commercial importance.
Between the late 3rd and early 4th centuries AD, the city perhaps experienced a period of economic crisis. New construction declined, and the ancient settlement shrank with the abandonment of entire areas, reused as burial grounds (Su Cuguttu), and the obliteration of important road sections (San Paolo). In the 5th century AD Olbia may have been subjected to a Vandal incursion, as evidenced by the destruction of an imperial naval fleet, the recently discovered wrecks of which can be dated to this period. Despite the decline in population during the Late Antiquity period, there are evidence of renovations to public buildings between the 4th and 5th centuries: the restoration of a tower in the northern sector of the walls and the reconstruction of a ruined structure mentioned in an inscription but not identified. The Roman necropolis occupied an area to the north of the ancient city, in the area that today extends from Via Roma to Via Fausto Noce. Another, later necropolis, dated to the 4th-6th centuries AD, was discovered in what was once the ancient urban area, in the locality of Su Cuguttu, located between Via Acquedotto Romano and Via E. Nenni.

History of the Excavations
The first investigations into the city's origins took place in the early 17th century and focused on the cemetery areas near the church of San Simplicio. In the first half of the 19th century, archaeological research began, aimed at acquiring material evidence, which was then transferred to both museums and private collections in Italy and abroad. Canon Giovanni Spano chronicled this activity, which led to numerous discoveries, from 1855 to 1876. From 1880 to 1884, Pietro Tamponi compiled a series of important notes on the archaeological discoveries made in Olbia and its surrounding area. Superintendents Antonio Taramelli in the early decades of the 20th century and Doro Levi in ​​the 1930s also repeatedly engaged in archaeological excavations. Dionigi Panedda's work in the 1950s was particularly important, resulting in the two volumes on Olbia in "Forma italiane." From 1958 to 1977, the city was the subject of sporadic excavation and restoration projects, such as those of the first Superintendent of Antiquities for the Provinces of Sassari and Nuoro, Guglielmo Maetzke, between the late 1950s and 1966, and those of Enrico Acquaro in the 1970s. In the years that followed, up until 1990, the Archaeological Superintendency's protection became systematic and continuous. Since 1990, research and in-depth knowledge of the area has been carried out in Olbia, which also includes the monitoring and recovery of archaeological heritage from sporadic excavations both on land and underwater. Unfortunately, the destruction of the ancient city's structures has paralleled the development of the modern city. Most of the excavations in the urban area alone have, and still have, emergency characteristics (fifty in number from 1980 to 1994, under the direction first of Antonio Sanciu and then of Rubens D'Oriano). In 1992, an emergency excavation uncovered an important burial site in the Su Cuguttu area. In July 1999, during construction of a tunnel beneath sea level, the remains of what the three-year archaeological excavation, conducted by Rubens D'Oriano, located along the coastline, identified as the wrecks of ancient ships and their cargoes.

Bibliography
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