Terracina is an Italian city and comune of the province of Latina, located on the coast southeast of Rome on the Via Appia ( by rail). The site has been continuously occupied since antiquity. Terracina appears in ancient sources with two names: the Latin Tarracina and the Volscian Anxur. The latter is the name of Jupiter himself as a youth (Iuppiter Anxur or Anxurus), and was the tutelary god of the city, venerated on the Mons Neptunius (current Monte S. Angelo), where a temple dedicated to him still exists (see below). The name Tarracina has been instead pointed out variously as pre-Indo-European origin (Ταρρακινή in ancient Greek), or as Etruscan (Tarchna or Tarchuna, the name of the Tarquinii family): in this view, it would precede the Volscian conquest. Terracina occupied a position of notable strategic importance: it is located at the point where the Volscian Hills (an extension of the Lepini Mountains) reach the coast, leaving no space for passage between them and the sea, on a site commanding the Pontine Marshes (urbs prona in paludes, "a city surrounded by marshes", as Livy called it) and also possessing a small harbour. During the 600s BC, it joined the Etruscan League of twelve cities. In 509 BC Terracina was already under Roman supremacy as reported in the 1st treaty between Rome and Carthage. It was soon re-occupied by the Volsci and was not included in the list of the Latin league of 499 BC. In 406 it was recaptured by the Romans then lost in 402 and recovered in 400, unsuccessfully attacked by the Volsci in 397, and finally secured by the establishment of a colony of Roman citizens in 329 BC as Colonia Anxurnas. As a colonia maritima the town frequently appears in history. The construction of the Via Appia in 312 BC added to its importance: the road at first crossed the hill at the back of the promontory by a steep ascent and descent. An attempt was made in 184 BC to get round it (by censor Lucius Valerius Flaccus) on an embankment thrown out into the sea: but it was probably not until early in Trajan's time (98-117 AD) that a cut in the rocks at the foot of the promontory (Pisco Montano) finally solved the problem.