This isolated park is home to that peculiarly Madagascan landform, the tsingy, a dense forest of jagged rocky pinnacles interwoven with deep canyons filled with streams and trees. It's a bit like visiting the more-famous Tsingy de Bemaraha, but without the crowds. Trails weave among the rocks, and rope bridges cross the canyons.
There are three circuits through the park. The 70km Circuit Ambovonomy combines walking with 4WDing and there are fine panoramic views and a good chance of seeing Decken's sifaka or red lemurs. Circuit Mandevy (70km) is similar, with good baobab views, while the Circuit Antsifotra (60km) is also similar, if slightly shorter and with less chance of spotting lemurs. Most circuits take four to six hours.
Other lemur species include eastern lesser bamboo lemur, fork-crowned lemur, grey mouse lemur, Milne-Edwards' sportive lemur, fat-tailed dwarf lemur and the oh-so-elusive aye-aye. More than 80 bird species have also been recorded here.
To get here, it's a rough 150km, eight-hour 4WD expedition from Katsepy to Soalala, from where it's a further 50km south. Count on four days' round trip from Majunga, plus time spent here.