Karst Characteristics


Think karst. Think common.

About 10% of the Earth's surface is Karst, and 25% of the world's population lives in a karst area.

happy caver

Water Required

Water and caves go hand in hand. Blue River flows through the heart of Indiana’s karst area.

another fun activity

Sinkholes Galore

One square mile near the town of Orleans in Southern Indiana has 1,022 mapped sinkholes!

a local bed and breakfast room

Formation Creation

Thousands of cave formations; stalactites, stalagmites, draperies, and others can form.

county tourism graphic

Tons of Breakdown

Monument Mountain in Wyandotte Cave is one of the world’s largest piles of breakdown.

What’s the story on Karst?

Back to top ↑

Karst’s Origin

The term karst was first used to describe an area of the Dinaric Alps in Yugoslavia. It is now used to refer to any similar topographical region throughout the world. In the United States, karstlands are located in Southern Indiana, Kentucky, Central Missouri, and Florida. These regions are characterized by underlying limestone or other soluble rocks. Acidic water gradually dissolved these underlying rocks, leaving behind an underground drainage system that includes…

  • sinkholes
  • sinking or disappearing streams
  • seeps
  • swallow holes
  • springs
  • caves

Helpful Karst Links:

Indiana Geologic Survey
Indiana Karst Conservancy
National Speological Society

Blue River’s claim to fame.

Back to top ↑

Blue River Basin

The Blue River Basin of Southern Indiana is a karst region that has over 1,000 caves. This basin includes two spectacular show caves: Wyandotte Cave and Marengo Cave. It is home to over 100,000 endangered Indiana bats and other rare species of animals. It also exhibits such rare karst habitats as limestone glades, chert barrens, and upland sinkhole swamps.

More on Blue River:

Canoe on Blue River

Sinkhole Preservation

Back to top ↑


A sinkhole is a basin that forms when limestone is dissolved and the soil layer “falls” into the resulting depression. They are usually shaped like a funnel or bowl. A sinkhole that has an open bottom can swallow entire creeks and streams.

Water Contamination

The ground water entering the sinkholes and caves in a karst landscape can travel underground quite rapidly, up to several miles a day. Water can easily become contaminated since the surface water flows directly underground and is not filtered by soil and bedrock. This can threaten drinking water by transporting contaminants to wells and springs in the area.

Here are some guidelines to prevent water contamination.

  • Do not use fertilizers, pesticides, and other chemicals within 100 feet of a sinkhole.
  • Do not dump garbage, debris, and other wastes into a sinkhole.
  • Leave a wide buffer of trees and vegetation around a sinkhole.
  • Use fences to keep livestock away from a sinkhole to prevent contamination by animal wastes.
  • Contact an experienced geologist before attempting to fill or seal a sinkhole.