Interior of cave
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Speedwell Cavern in Derbyshire, England, a karst cave

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Karst caves, also known as solution caves, are the most common type of cave.[1]

Karst is a landscape typically formed by the solution of carboniferous rocks such as dolorite, limestone or gypsum by the action of rainwater,[2] which is weakly acidic owing to the presence of carbonic acid, H2CO3.[1] The resulting collapse of those rocks as the result of their erosion creates features such as sinkholes, caves, and underground streams and rivers.[3]