Cansiglio is a plateau of the Carnic Prealps which covers a wide area between the provinces of Belluno, Treviso and Pordenone. At its feet lies the plain of two regions, Veneto and Friuli Venezia Giulia. The Cansiglio Plateau borders with the Alpago area to the North, with Mount Cavallo to the East and with the Val Lapisina to the West.
The origin of the Carnic Prealps dates back 80 million years (Upper Cretaceous), when the area was covered by a shallow sea. There were islands populated by small animals and plants (shellfish, corals, sponges, algaes) which created a limestone reef. Nowadays fossils are found along an area one-kilometre long that divides the territory in two in direction North-East South-West.
The Cansiglio Plateau was affected by a geological phenomenon called Carsism, a slow erosion of calcium carbonate contained in limestone rocks. Those rocks are as a result prone to fractures due to tectonic movements.
Several sinkholes are visible on the surface of the ground which widen at the bottom. Among them the "Bus (Hole) de la Lum" (187m deep) and the "Bus (Hole) della Genziana" (587m deep). The accretion of impermeable soil and clay on the bottom of the pits and the saturation of the subsoil during the rainy season transformed the sinkholes into ponds called "lame".
The plateau has the shape of a big basin surrounded by mountains, as for instance Mount Millifret (1,157m) and Mount Pizzoc (1,565m) in the municipality of Fregona. Due to the Thermal Inversion phenomenon, the central part of the plateau is now a wide dell of meadows used for pasturage. With time the area has increased in size due to deforestation.
The forest surrounds the dell and, from 1,100 to 1,400 metres above sea level, consists mainly of stately beeches (Fagus Sylvatica), some reaching 30 metres in height. The beechwood reaches its best on the Southern side of Cansiglio, on the slopes of Mount Pizzoc and Mount Millifret, with a splendid display of colours according to seasons. At a lower sea level, where it's colder due to the Thermal Inversion effect, beeches are found together with Silver Firs (Abies Alba) and Spruces (Picea Excelsa).
The Cansiglio Forest was of great economic influence at the time of the Serenissima (Republic of Venice). The beech wood was used to make oars, for timber and coal. In 1548 the Council of the Ten named the forest as the "Gran Bosco de Reme di San Marco" (the Great Wood of the Oars of Saint Mark) and assigned the supply of wood to the production of oars for the galleys and timber for the Arsenal of Venice (the shipyard of the Venice Republic). A Forest Overseer was appointed and an Oarsmen Guild was founded with the responsibility for the management of the forest, the cutting of the wood and the building of the oars.
The undergrowth of the Cansiglio Forest is rich in vegetable species suitable for shaded areas, such as ferns, wood anemones (Anemone Nemorosa), green hellebores (Helleborus Viridis), wood sorrels (Oxalis Acetosella), creating a mixed vegetation pervaded every year in March by the intense fragrance of the mezereon (Daphne Mezereum), a small shrub with colourful flowers. Seasonal flowers like gentians (Gentiana Verna, Gentiana Clusii) and crocuses (Crocus Albiflorus) add varied colour nuances to the open spaces.
The flora heritage of the Cansiglio Forest is of profound interest to botanics. The Cansiglio Mount was free from ice during glaciations and became a suitable haven for flowers, favouring the survival of endemic varieties like the silvery crane's bill (Geranium Argenteum). Wetlands such as "lame" (a kind of pond) and marshes are of notable interest and scientific importance, and due to their vulnerability they are protected by law.
Among the several animal species populating the Cansiglio Forest, the deer (Cervus Helaphus) is the predominant one. Found mostly on the North-Eastern area of the plateau, during the winter season deer live on the Eastern slopes, while they move to Valmenera for the male fights during the love season.
The roe deer is easily spot while grazing at twilight. Other species present are the fallow deer (Dama Dama), introduced by man in this area, the lynx (Felis Lynx) and apparently traces were found of the brown bear (Ursus Arctos).
Further mammals present are the European hare and the Mountain hare, the squirrel (Sciurus Vulgaris), his food being the spruce pine, and the dormouse (Glis Glis). Nocturnal species are the marten (Martes Martes) and the beech marten (Martes Foina), the European badger (Meles Meles) and the least weasel (Mustela Nivalis). The fox (Vulpes Vulpes), the only representative of the canids (Canidaes), hunts at night and digs its den close to sinkholes.
The Cansiglio area is such a perfect habitat for many kinds of birds that it is virtually impossible to make a thorough list. Among the permanent species are the finch, the hooded crow and the white wagtail in the open areas; the jay - whose croaky cry is easily recognised - the coal tit, the crested tit, short-toed treecreeper, the bullfinch, the red crossbill, the firecrest, the goldcrest, the robin, the long-tailed tit inside the forest; the goldfinch, the citril finch, the blackbird, the mistle thrush, the ring ouzel on the edges of the wood. The black, red and green woodpecker are also present, together with many birds belonging to the Passeriformes. Among the migratory birds one can spot some Anatidaes like the mallard, the garganey, in summer the skylark, thew whinchat, the starling, the tree pipit, the black redstart, the wren, the blackcap, the red-backed shrike and many others. Some birds of prey are present, such as the common buzzard, the kestrel, the goshawk, the sparrowhawk, the tawny owl, the pygmy owl, the boreal owl, the eagle owl, and even the golden eagle (Aquila Chrysaetos).
Reptiles are rare in the Cansiglio woods, but on the karstic plains just above, such as the Col dei Scios area or on Mount Pizzoc, one might meet the viper, the green and the common lizard. Wet and grassy areas attract the Aesculapian snake, the grass snake, the slow worm.
High humidity and stagnant waters foster the life of amphibians: the alpine and the great crested newt - which live in water - the black salamander, the common frog and the green frog.