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Cassia Silent City of Rocks
Cassia Silent City of Rocks contains monolithic landforms created by exfoliation processes on exposed massive granite plutons. It is the best example of bornhardts (weather-resistant rock left standing after erosion of surrounding rock) in the country.
Location: Cassia County, ID
Year designated: 1974
Ownership: Federal, State, Private
For additional information see:
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