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Geography

Why Limestone Karst Landscapes Develop Sinkholes and Underground Drainage Systems

Quick fact

Some karst regions have more than a thousand sinkholes per square kilometer, and extensive cave networks can stretch for hundreds of kilometers beneath the surface.

Why this is interesting

Have you ever seen a lake that suddenly drains away, or a cave that swallows an entire river? In karst landscapes, water can flow right through solid rock as if it were a sponge.