Karst is a type of landscape characterized by the presence of springs, sinkholes, losing streams and caves, created as groundwater dissolves soluble rock such as limestone or dolomite. 

Missouri has more than 7,500 caves
Losing Streams
Losing streams lose water to the groundwater system through bedrock openings
The state has more than 16,000 known sinkholes
Missouri has more than 4,400 springs