The Isalo Massif has been eroded by wind and water, resulting in deep canyons, sandstone domes, flat-topped mountains and "runiform" mountains - steep sided outcrops that have been dissected into odd-shapes.
The Isalo Massif has been worn down by wind and water, resulting in deep canyons, sandstone domes, flat-topped mountains and "runiform" mountains - steep sided outcrops that have been cut into unusual shapes.