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Cold Water Cave
Cold Water Cave is an exceptional example of an extensive cave system well decorated with speleothems. It contains numerous vertical shafts and an unusually large, meandering underground stream that courses along most of the approximately 7.3 miles of cave passageways. Relatively young in geologic terms, the cave appears to be enlarging more rapidly than most caves in the United States. The cave atmosphere is also unusual for its typically low oxygen content and extremely high carbon dioxide content.
Location: Winneshiek County, IA
Year designated: 1987
Please remember, National Natural Landmarks (NNLs) are not national parks. NNL status does not indicate public ownership, and many sites are not open for visitation.
Last Updated: June 28, 2012