Soluble rocks dissolve and leave a distinctive landscape behind. Karst is terrain shaped by the dissolution of limestone, dolomite, or other soluble rocks. Sinkholes, disappearing streams, caves, and towers are characteristic features.

Slightly acidic water enlarges fractures into conduits and caves. Surface drainage is often captured underground, leaving dry valleys. Tower karst and cockpit karst develop in tropical regions with intense dissolution. The resulting landscapes can be both scenic and hazardous.

Karst aquifers are highly productive yet vulnerable to rapid contamination because water moves quickly through enlarged openings. Engineering on karst requires careful assessment of sinkhole risk. Classic karst regions include parts of the Dinaric Alps, southern China, and the Yucatán Peninsula.

• Landscape formed by dissolution of soluble rock
• Features sinkholes, caves, and underground drainage
• Common in limestone regions
• Creates productive but vulnerable aquifers