Today called "Selva di Circe", is the only example of plain forest with a natural vegetation dominated by the presence of deciduous oaks; despite the hydraulic reclaiming, given the geo-morphological features of the territory where it vegetates, an old coastal dune which consolidated during the centuries shows still today wide areas called "piscine", seasonally flooded by meteoric waters. The uniqueness of this environment led to its inclusion in 1977 in the net of the M.A.B UNESCO Programme for the Biosphere Reserves (Man and Biosphere).
A calcareous relief reaching 541 meters above sea-level. It is without a doubt the most particular landscape element of the whole Pontina area. Its inner slope, called "quarto freddo" is covered by a big thermophilous forest, while on the opposite slope, the so-called "quarto caldo", facing South and next to the sea, more extreme environmental conditions determine a less luxuriant Mediterranean vegetation with pioneer halophilic species (saltiness, dryness, and high temperature resistant), high and low maquis. The presence of several caves on different levels of the slope facing the sea makes this area interesting both from a geo-speleological point of view, for the finds which have been discovered, and from a prehistorical point of view.
The Coastal Dune extends itself along the coast, from the slopes of the promontory and for about 25 km northwards to Capo Portiere. It is a geologically and vegetationally delicate area consisting in a continuous series of sandy reliefs reaching a width of 250m. Also in this case we can distinguish a less protected sea-side slope with a pioneer halophilic vegetation and an inner slope which is protected by the sea wind full of saltiness, which houses high and low Mediterranean maquis.
Next to the dune and under the lee of it there is a wetland consisting in a series of four Coastal Lakes (Paola or Sabaudia Lake, Caprolace Lake, Monaci Lake, and Fogliano Lake) and Wetlands, which are seasonally flooded and which together with the grasslands-pastures form a group of territories which has been declared "Wetland of International Interest" according to the Ramsar Convention (Iran 1971): the brackish lagoons and the areas which become seasonally marshy, offer an ideal area for the different rest, wintering, or nesting needs of several species of migratory birds.
Zannone Island, an insular appendix of Circeo Park (from 1979), geographically belongs to the western group of the Pontine islands (Ponza, Gavi, Palmarola) which together with Ventotene and Santo Stefano make the Archipelago of Ponziane Isles. Although it is rather small (about 100 ha), in addition to interesting floristic and faunistic endemic species, a particularly luxuriant Mediterranean vegetation which is well preserved because of the limited historical anthropical presence with a resulting very little damage to its territory. In addition, it is an essential reference point for the migratory birds, because of its geographical position and of its quiet and uncontaminated area.
The area of Borgo di Fogliano, on the shores of the homonymous lake, is situated in the northern section of the Park, in the Municipality of Latina.
It preserves not only naturalistic, but also historical and
architectural features: scrapers, arrowheads, and other traces of the
human presence since prehistory have been found in the area.
The
Romans carried out important land reclamation activities, transforming
the area into an important breeding and fishing center, building
swimming-pools and canals to better exploit the richness of the lake.
The archaeological sites characterizing the area are probably one hundred.
They give us the opportunity to have a rather good knowledge of the
Roman settlements gravitating around the Circeo promontory.
Ancient road lay-outs, urban and defensive structures,
Circeii, religious and civil buildings, necropolis, the harbour area of
Torre Paola, the complex of villas on the shores of Sabaudia Lake,
Domitian's Imperial Villa, the rests of the area of Borgo di Fogliano
and of the island of Zannone represent the distinctive historical
heritage of Circeo Park.