17, II), the Hernici in the Trerus valley, Satricum and Glanica in the Pomptine marshes.
At Forum Appii it entered the Pomptine Marshes; that this portion (19 m.
Of the Pomptine Marshes.
The presence of the former was due to the fact that it was the starting-point of a canal which ran parallel to the road through the Pomptine Marshes, and was used instead of it at the time of Strabo and Horace (see APPIA, VIA).
Its position, at the point where the Volscian Hills reach the coast, leaving no space for passage between them and the sea, commanding the Pomptine Marshes (urbs pron g in paludes, as Livy calls it) and possessing a small harbour, was one of great strategic importance; and it thus appears very early in Roman history.
The summit is occupied by a massive terrace, supported by arcades of fine opus incertum (traditionally, but wrongly, called the palace of Theodoric) on all sides except the E., and commanding a magnificent view seaward over the coast and over the Pomptine Marshes.
Of the lower town by the harbour, which had buildings of some importance of the imperial period (amphitheatre, baths, &c.), little is now visible, and its site is mainly occupied by a new quarter built by Pope Pius VI., who restored the Via Appia through the Pomptine Marshes.
The region of the Pomptine Marshes occupies almost the whole tract between the sandy belt on the sea-shore and the Volscian mountains, extending from the southern foot of the Alban Hills below Velletri to the sea near Terracina.
The district sloping down from Velletri to the dead level of the Pontine (Pomptine) Marshes has not, like the western and northern slopes of the Alban Hills, drainage towards the Tiber.
In 358 B.C. Roman preponderance in the Pomptine territory was shown by the formation of the tribus Pomptina and Publilia, while in 338 and 3 2 9 respectively Antium and Tarracina became colonies of Roman citizens, the former having been founded as a Latin colony in 494 B.C.
Velletri has a fine view of the Volscian mountains and over the Pomptine Marshes to the Circeian promontory.
POMPTINE MARSHES, a low tract of land in the province of Rome, Italy, varying in breadth between the Volscian mountains and the sea from 10 to 16 m., and extending N.W.