Limestone in this area was originally full of minerals that gave it a deep red to purple color. But rain and water leached out those minerals changing the limestone lighter shades of color to pure white if all minerals were leached away. This particular grotto of hoodoos is in a place where water has leached the limestone to various shades of pink.

The capstones of these hoodoos are unique in that they consist mostly of a densely packed conglomerate of cemented small pebbles. A closeup of one of them showing the pebbles is in this collection.
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