The importance of the area was noted by explorers in the early 20th century, and in 1927, the central part of the mountain range was declared a "Strict Nature Reserve".

[2][3] In 2007, the park became part of the Rainforests of the Atsinanana World Heritage Site.

[5][6] The Ampanasana, Iantara, Menarahaka and Zomandao rivers run through the reserve.

In the south and west the Bara people graze cattle on the savannah and in the valleys and on the ridges, while in the east the Bara Haronga grow rice, and the Betsileo people have developed an irrigation system on the mountain flanks of the north for rice cultivation.

[5] The park is one of the most biologically diverse places in Madagascar, with many endemic species.