This remote reserve ranges from the north-east coast of Madagascar to the Analamerana karstic plateau with elevations of 1,185 metres (3,888 ft) in the Soanierana Ivongo District, Analanjirofo region.

The reserve headquarters are in Soanierana Ivongo and the park is only accessible by canoe along the Marimbona River.

[2][3] The reserve is mainly covered by dense deciduous dry forest and is the last place for the critically endangered lemur, Perrier's sifaka (Propithecus perrieri).

[4] The white-breasted mesite (Mesitornis variegata) is one of the fifty-five species of endemic birds found on the reserve, and is also one with a very restricted distribution, known from only six sites within the country.

[4] Other rare birds are Van Dam's vanga and the Madagascar pond heron.