This is a list of the National Register of Historic Places listings in St. Mary's County, Maryland.
This is intended to be a complete list of the properties and districts on the National Register of Historic Places in St. Mary's County, Maryland, United States. Latitude and longitude coordinates are provided for many National Register properties and districts; these locations may be seen together in a map.
There are 32 properties and districts listed on the National Register in the county, including 3 National Historic Landmarks.
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