Monti Ausoni in the context of "Pico, Italy"

The Pontine Marshes (/ˈpɒntaɪn/ PON-tyne, US also /ˈpɒntiːn/ PON-teen; Italian: Agro Pontino [ˈaːɡro ponˈtiːno], formerly also Paludi Pontine; Latin: Pomptīnus Ager [sg.] by Titus Livius, Pomptīna Palus [sg.] and Pomptīnae Paludes [pl.] by Pliny the Elder) is an approximately quadrangular area of former marshland in the Lazio Region of central Italy, extending along the coast southeast of Rome about 45 km (28 mi) from just east of Anzio to Terracina (ancient Tarracina), varying in distance inland between the Tyrrhenian Sea and the Volscian Mountains (the Monti Lepini in the north, the Monti Ausoni in the center, and the Monti Aurunci in the south) from 15 to 25 km (9+1⁄2 to 15+1⁄2 mi). The northwestern border runs approximately from the mouth of the river Astura along the river and from its upper reaches to Cori in the Monti Lepini.

The former marsh is a low tract of mainly agricultural reclaimed land created by draining and filling, separated from the sea by sand dunes. The area amounts to about 80,000 hectares (200,000 acres). The Via Appia, a Roman military road constructed in 312 BC, crosses the inland side of the former marsh in a long, straight stretch flanked by trees. Before then, travelers had to use the Via Latina along the flanks of the mountains; Terracina could not be reached across the marsh.

The Monti Aurunci (or Aurunci Mountains) is a mountain range of southern Lazio, in central Italy. It is part of the Antiappennini, a group running from the Apennines chain to the Tyrrhenian Sea, where it forms the promontory of Gaeta. It is bounded to the north-west by the Ausoni Mountains, to the north by the Liri river, to the east by the Ausente, to the south-east by the Garigliano and to the south by the Tyrrhenian sea. The line between the Aurunci and the Ausoni has not been clearly established but the Aurunci are considered by convention to be east of a line through Fondi, Lenola, Pico, S. Giovanni and Incarico. Altitudes vary from hills to the 1,533 m of Monte Petrella. Main peaks include the Redentore (1,252 m) and Monte Sant'Angelo (1,402 m). They include a regional park, the Parco Naturale dei Monti Aurunci, created in 1997.

The mountains take the name from the ancient tribe of the Aurunci, an offshoot of the Ausoni. Both tribes were derived from the Italic people who were called by the Romans the Volsci; hence, the Monti Lepini, the Monti Ausoni and the Monti Aurunci are also called the Volsci or Volscian Chain. Coincidentally they are all of the same karst topography and have the same orogeny, which is not quite the same as the Apennines proper.

The Monti Lepini (Italian: Lepini mountains) are a mountain range which belongs to the Anti-Apennines of the Lazio region of central Italy, between the two provinces of Latina and Rome.

The range borders to the north with the Colli Albani, to the south-east with the Amaseno Valley, to the south with the Monti Ausoni and to the west with the Pontinian Plain. The highest peak is the Monte Semprevisa (1,536 m).