The origins of the 'Pirin' National Park go back to 1962, but during the ensuing years its boundaries have been enlarged and altered several times. Today the 'Pirin' National Park occupies a total area of 40,332.4 hectares, and covers about 15% of the Pirin Mountains. About 43% of the 'Pirin' National Park comprises open terrain, in the form of mountain pastures and meadows, as well as rocky peaks, ridges and screes. The remaining 57% of the national park is forested, in particular by extensive areas of Dwarf Mountain Pine (Pinus mugo), Macedonian Pine (Pinus peuce), Scots Pine (Pinus sylvestris) and Norway Spruce (Picea abies).There are two nature reserves within the 'Pirin' National Park, accounting for about 14.9% of its total area:
The 'Bayuvi Dupki - Dzhindzhiritsa' Reserve is a UNESCO Biosphere Reserve, whilst the 'Pirin' National Park as a whole was designated as a UNESCO World Heritage Site in 1983.
The flora of the 'Pirin' National Park is very rich, some 1315 species of higher plants which represents about one third of the total number of species found within Bulgaria. These include 18 local Pirin endemics (found nowhere else in the world), 17 Bulgarian endemics (known only from Bulgaria) and 86 Balkan endemics (growing only on the Balkan Peninsula).
The 'Pirin' National Park also has an extremely diverse and interesting fauna. The invertebrate fauna is still only partly studied, but already over 2000 species have been found. These include 9 species of dragonfly (Odonata) and many interesting butterflies (Lepidoptera).
The vertebrate fauna of the 'Pirin' National Park has been studied in much greater detail, and includes 6 species of fish, 8 species of amphibians and 11 species of reptiles. During recent studies, some 159 species of birds have been found within the national park itself, of which 110 species have been recorded as breeding. This number increases to 129 nesting species if one includes the species that have been recorded breeding in adjacent areas and which fall within the 'Pirin' Important Bird Area (IBA). Some 45 species of mammals have been recorded in the 'Pirin' National Park. These include 16 species of bats, 16 species of small mammals (insectivores and rodents), and 13 species of large mammals, of which 9 species are carnivores including brown bear and wolf.
