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Bijou Hills is an excellent example of an erosional remnant of soft clays and shales capped by a channel sandstone and quartzite.
Location: Charles Mix County, SD
Year designated: 1976
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