Frosinone:
The province of Frosinone has a surface of 3.239 Sq km, with 91 municipalities and a total of 478.393 inhabitants.
The territory is divided in three morphologic main areas: the Apennines relieves of the Simbruini Mounts, the Lepini Mounts until the Meta Mainarde; the pre-Apennine relieves of the Ausoni Mounts, Aurunci Mounts and part of the Lepini Mounts; the Valle Latina, between the Apennines and the pre-Apennines.

From North to North-East the Apennine relieves form the natural frontier with the regions of Abruzzo and Molise. They comprise, with summits above the 2000 meters: M. Viglio (2156 m), Pizzo Deta (2041 m), M. Meta (2241 m).
The Lepini, the Ausoni and the Aurunci Mounts run West to South. These mountain groups have a homogenous geographic structure.

In fact, until 1700 they were united under the name of Monti Volsci. Amongst the higher summits are: M. High (1416 m), M. Caccume (1095 m), M. Calvilli (1116 m) and M. Fammera (1184 m).
The karst landscape is characterized by the beautiful and evocative Grotte di Pastena, formed from a fossil branch that extends under the cliff for approximately 880 meters and an active branch instead approximately 2000 meters long.
The Grotte of Collepardo represent a further example of the karst phenomena of Ciociaria. The Valle Latina, an extremely wide depression, devides the Lepini, the Ausoni and the Aurunci Mounts from the Simbruini, the Ernici, the Meta and the Mainarde Mounts.

The Valle Latina narrows in the North-West of Frosinone and widens in the South-East, until the depression of the Cassino area, to the border with Campania. In Northern Frosinone, it is known as Valle del Sacco, just because of the River Sacco flowing there.
The river Sacco flows in the Liri. The Liri crosses the area of Sora, of Isola del Liri and here gives origin to beautiful waterfalls.
Nearly the totality of the mount relieves of the province of Frosinone are protected territories: the area of the Abruzzo National Park belonging to Lazio, the Regional Nature Reserve of Fibreno, the Regional Park of the Simbruini Mounts and the Regional Park of the Aurunci.

Besides the naturalistic beauties, the Province of Frosinone is very rich in archaeological and artistic treasures: the Acropoli’s remains of Alatri and the Cyclopic Walls among the others. It is also important to underline the presence of Monasteries like, for example, the Certosa of Trisulti and, above all, the huge Abbey of Montecassino.

http://www.turislazio.it/index.php/turismo_eng/the_cities_of_lazio/province_of_frosinonev