According to Cvijic, there are four stages in the evolution of landforms in a karst region: youth, maturity, late maturity and old age.

(i) Youth:

The youth begins with surface drainage on an initial limestone surface or one that has been laid bare and is marked by a progressive expansion of underground drainage.

This stage is characterized by the presence of such erosional features as lapies and dolines. Large caverns are seldom to be seen and underground drainage is in its initial stage. There is no formation of large caverns.

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(ii) Mature Stage:

This stage begins with the maximum development of underground drainage. Large number of caves and caverns characterize this stage. Surface drainage is limited to short sinking creeks which end in swallow holes and blind valleys.

This stage is characterized by the development of thousands of swallow holes and dolines. This stage represents the maximum develop­ment of karst topography with all its charac­teristic landforms.

(iii) Late Maturity Stage:

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Late maturity in the Karst cycle begins with the decay and decline of karst topography. Various feature of the karst topography expand and coalesce to form uvalas. Poljes with their hums are to be seen on the surface.

(iv) Old Stage:

With the beginning of the old stage there is return to surface drainage. Now, the caverns collapse, leaving open, flat-floored valleys. Solution activity has removed most of the limestone formations.

The karst windows, natural tunnels and bridges and other solution features disappear. Only isolated knolls remain as remnants of the former limestone surface.