During the reign of [[Hadrian]] the city was renamed Colonia Ulpia Traiana Augusta Dacica Sarmizegetusa. Between 222 and 235 the colony was called a metropolis. The name was found on a stone inscription that reads "To Caius Arrius Quadratus, son of Gaius Arrius Antoninus, acting praetor of the emperor in Colonia Ulpia Traiana Augusta Dacica Sarmizegetusa." Gaius Arrius Antoninus bore the title [[...|legatus pro praetore]], which was the official title of the governor of some imperial provinces of the [[Roman Empire]].
== Location ==
The settlement was built at a distance of 8 km from [[Tapae]], a pass between [[Banat]] and [[Transylvania]] (today known as the Iron Gates of Transylvania). The choice was based on the military and economic advantages given by the natural barrier represented by the Retezat Mountains in the south and Poiana Ruscă Mountains in the north. The territory of the metropolis extended from [[Tibiscum]] to [[Micia]] and to the [[Jiu canyon]], the city being protected by several [[castra]]: [[Tibiscum (castra)|]], [[Pons Augusti (castra)|]], [[Micia (castra)|]] and .
The city was crossed by the imperial road from the [[Danube]] that linked the north of the province with [[Porolissum]] (Moigrad).
== Archeological site ==
Today, the archeological site contains the following remains:
* Gladiator school
* [[Nemesis (mythology)|Goddess Nemesis]] Temple
* [[Bacchus|Liber Pater]] Temple
* Gods [[Aesculapius]] and [[Hygieia]] Temple
* Temple Basilica
* Great Temple
* [[Silvanus (mythology)|God Silvanus]] Temple
* Glass blowers' workshops
* Financial procurator's office