This story appears in the November 2009 issue of National Geographic magazine. The lizard moved in frightened rhythms across the sun-blasted stone. A few quick steps, a turn of its boxy head. Then ...

But penitentes and stone forests are actually quite different in terms of the mechanisms involved in their formation. "I think the similarities are pretty superficial," said Ristroph.

The most famous stone forests can be found in China and Madagascar, but are seen dispersed all over the world, and each have rich cultural significance. The Yunnan province in southwestern China is ...

Examples include the Stone Forest, or Shilin, of Kunming, China, the jagged pinnacles of Tsingy de Bemaraha National Park in Madagascar, and the Pinnacles of Gunung Mulu in Malaysia.

There's a crazy landform in Madagascar called a tsingy, which, euphemistically translated from Malagasy, means "where one cannot walk barefoot." It's basically a treacherous forest of limestone ...