Ankarana is best known for its serrated, dark-grey tsingy (the word means 'walking on tip-toes') and its caves, and there are a variety of circuits taking in the highlights. The park is split in two halves, which are distinct and not easily linked, so plan on two days to visit both sides.
The eastern half is the most accessible, via the village of Mahamasina, and the best place to admire the strange-looking tsingy. The easiest way to see these surreal pinnacles is to do the two- to three-hour Grotte des Chauves-Souris (Bat Cave) circuit. This impressive cave has superb stalactites and stalagmites, and thousands of bats; nearby is a small viewpoint from where you can look over the Petits Tsingy.
The route to the Grands Tsingy is longer – five hours return – with some interesting sights on the way, including Perte des Rivières, a massive rock chasm into which three of the park’s rivers plunge during the rainy season (they emerge 20km later in the Mozambique Channel). There are some good viewpoints and a rope bridge to cross. The hike to the pretty Lac Vert is the longest circuit (nine hours in total) and takes in all the main sights in the eastern half of the park.
The western half of Ankarana is different and only accessible from June to December. Here the focus is on three sets of caves, Grotte Squelette (Skeleton Cave), Grotte Cathédrale (Cathedral Cave) and Grotte d’Andrafiabe, which you can visit through a subterranean circuit (if this doesn’t appeal, another circuit links two of the caves via a ‘normal’ path). There are beautiful canyons along the way, including Canyon d’Andohalambo.