The Poloniny National Park is proud of its unique, Carpathian beech great-forests which are inscribed on the List of UNESCO World Cultural and Natural Heritage.
Thousand-year old great-forests
Beech and fir-beech forests cover up to 80% of the area and, therefore, Poloniny have deserved to be called 'the green lungs of Europe'. What is interesting here is the largest concentration of great-forests that create a chain of "small islands" of the original forest that is has been growing here for a thousand years. These are centuries-old fir trees, beeches, maples, and the something called 'dead tree' that creates a haven for mushrooms and Ural owl, white-backed woodpecker, and small flycatchers. Great-forests are concentrated in 10 independent sections. Four of them are located in Slovakia (Havešová, Rožok, Stužica – Bieszczady Mountains, Wyhorlat) and six in Ukraine.
The National Nature Reserve is valuable due to the high, old firs, beeches and mountain maples. The most valuable specimen here is the 300-year-old and 50-meter-high fir. Stužica is considered to be the finest and most extensive preserved Carpathian great-forest in Slovakia.
On the area of the Natural Reserve Havešová there are valuable lichens of great-forests with the occurrence of unique specimens of maples, ashes, elms and 250-year-old beeches reaching 50 meters in height. The area is a part of the Nastaz Mountains in Bieszczady.
Rožok and the Kyjevský Great-forest
These two areas are unique because here are old deciduous trees of great-forests, such as maple, elm, or ash.
Wyhorlat stretches along hogbacks of the Wyhorlat mountains, north of the Morskie Oko Lake. 240-year old beeches grow here.