Situated at 30km eastward Moramanga near the station of Périnet and the village of Andasibe , with an area of 840 ha for Perinet and 10 000 ha for Mantadia, these reserves localized inside a lateritic ground mountain of hills .

The climate is characterized by an average annual pluviometry near 1700 mm with a maximum in January . In dry season (from June to October) there are morning and nocturnal fog and intermittent fine rains.
Monthly average temperatures : minimum 14°C (August) and maximum 24°C (in January)

The reserve presents a canopy composed of Wenmania , Tambourissa, Symphonia, Dalbergia, Ravensara, and Vernonia .The sub humide evergreen forest presents a dense arborescent stratum . Typical genera are arborescent ferns (Cyathea) but also Dypsis, Plantago, Smilax, rubus,.... The epiphyts are in great number and composed of ferns , mosses , orchids (Bulbophyllum) and cactus (Rhipsalis) that is the unique cactus present in Madagascar and Africa.

At least eleven species of lemurs within the reserve : such the Indri Indri , the reddish-brown belly Lemur (Lemur rubriventer) or the gray Hapalemur (Haplemur griseus). The Lemur vari (Varecia Variegata) and the Propitheque with tiara (Propithecus diadema) are known of the surrounding forests and seem to reintegrate the reserve . A nocturnal walk allows to see many nocturnal lemur species such the woolly Avahi (Avahi laniger ) , the Aye Aye (Daubentonia madagscariensis) and the great Cheirogale (Cheirogaleus major). .
There are endemic carnivores as well as a rich fauna of micromammalians. The avifauna are near 109 counted species some of them extremly rare , such Eutriorchis astur (collected on several occasions in Analamazaotra in 1920 and 1930 ).Three of the land Rollers species that frequent the pluvial forest can also be seen in the reserve.