Caves of the Mananjeba Buttes
The Mananjeba Buttes comprise a group of three hills isolated from the Northern Ankarana by the widening and deepening of one of the main couloirs that cut the plateau. The northernmost butte is crossed by a side branch of the Mananjeba River. The central butte is crossed by the main stream of the Mananjeba and contains the second longest cave in the Ankarana: Ambatoharanana. No major cave has yet been found in the southernmost butte, but there is little doubt that a long cave network exists there.