Limestone Towers, Madagascar Photograph by Stephen Alvarez, National Geographic A city of limestone

Limestone Towers, Madagascar

Photograph by Stephen Alvarez, National Geographic

A city of limestone towers rises in western Madagascar. Sharp, steep, and brittle, the maze of rock in Tsingy de Bemaraha national park and reserve has repelled all but a few explorers and scientists, leaving large parts of the region—and countless resident creatures—unknown to humans.

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