National Natural Landmarks

Giant City Geological Area

Giant City Geological Area
Giant City Geological Area

Located within Giant City State Park, Giant City Geological Area is an exceptional example of gravity sliding, consisting of massive joint-bounded sandstone blocks of Pennsylvanian age. The site supports a rich flora including xeric oak woodlands, oak-hickory and mesic forests dominated by sugar maple.

Location: Union County, IL ; Union County, IL

Year designated: 1980

Acres: 54

Ownership: State

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Please remember, National Natural Landmarks (NNLs) are not national parks. NNLs are owned by a variety of public and private entities and allowing visitation is at their discretion. Many NNL sites maintain public websites where additional information may be found.

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