The paramount importance of this park is given by its floristic richness, amplified by the apparent vulnerability of mountainous ecosystems.
The Ceahlau Massif, wherein the park has been created, is placed in the north-central part of Eastern Carpathians, towards the western boundary of Neamt County. The northwestern boundary is Bistricioara River, the eastern one is the lake Izvorul Muntelui, while Bicaz River borders the park at south and two brooks (Pintec and Bistra) stand for the southwestern limit.
The vegetation is being stratified and comprises plants with different origins. Among inferior plants, lichens (141 species) and mosses (194 species) are frequent, two of them being endemic species for Ceahl0a0u. More than 1,100 species of flowering plants have been identified, of which 62 are Romanian endemic species, like: Ranunculus carpaticus, Hepatica transsilvanica, Campanula carpatica, Pedicularis baumgartenii, Hieracium pojoritense, Primula elatior ssp. leucophylla, Centaurea pinnatifida. Threatened species are Leontopodium alpinum, Nigritella rubra, Nigritella nigra, Cypripedium calceolus, yew.
Insects are the most representative invertebrates, the area being an important genetic centre for Europe. Stoneflies (Plecoptera) are represented by 72 species, of which 5 species have been described as new for the science; along with the 2 species of Hymenoptera - 36 species of ants, bees, and wasps can be found here. The stonefly called Arcinopterix comparata is regarded as a living fossil. Vertebrate fauna is represented by 90 species of birds, many of them being typical for the mountains, and some mammals: the chamois (Rupicapra rupicapra), which has been colonized here and also some predators like: lynx (Lynx lynx), wolf (Canis lupus), and brown bear (Ursus arctos). Triturus montandoni inhabits forest wetlands, being an endemic species in Eastern Carpathians.
The landscape is storied on many belts, due to the diversity of basal rocks (limestone and conglomerates placed on crystalline bedrock) and according to the altitude. The mountain is adorned with many peaks and ridges.
All activities that do not threat the ecological balance are permitted: dead trees are removed in the buffer zone, as they can block the tourists’ trails and grazing is permanently monitored. Tourism and research works are allowed.
