Karst landscapes occur around the world, though the formation varies a lot from place to place. In some locations, like Colossal Cavern in southern Arizona, and Colossal Cavern in Kentucky, karst-like conditions have resulted in limestone being dissolved almost exclusively underground, forming cave systems. Another famous karst system covers much of Mexico’s Yucatan Peninsula where huge sinkholes have opened throughout the area.

 Yucatan sinkhole >

Rainwater seeping through the soil and rock picks up carbon dioxide and becomes slightly acidic. This light acid dissolves through the limestone rock along cracks and other weaknesses. The weaknesses can follow the layers of horozontally, or cracks vertically, or both.

Karst most commonly occurs in limestone areas, but is known in several other rock surfaces including quartz.

On the island of Madagascar, off the southeast coast of Africa, karst landscape is very prominent in the Tsingy de Bemaraha National Park, and the Tsingy de Bemaraha Strict Nature Reserve.

The geologic history of the whole island is a fascinating subject, and I encourage you to do some investigation if you have any interest in the subject.

The Tsingys are karstic plateaus. Groundwater has dissolved the rock below the uplands, resulting in gouged caverns and fissures into the limestone. In the Tsingys, erosion has happened both vertically and horizontally. In western Madagascar, in and around the National Park and Nature Reserve, the erosion has created dramatic "forests" of limestone needles.

The word tsingy a Malagasy word for the karst badlands of Madagascar. The word can be translated into English as “where one cannot walk barefoot.”

< Karst landscape in Tsingy de Bemaraha National Park

Here's a scientific article on the formation of Malagasy karst.The origin of the Bemaraha tsingy (Madagascar) by Márton Veress, Dénes Lóczy, Zoltán Zentai, Gábor Tóth, Roland Schläffer