Relief shown by contours and spot heights. Alternate title in right lower margin: Philadelphia Co., Pa. "Map edited 1982." Pa. coordinate and UTM grids. Includes notes, index to 1:24,000-scale maps, and location map. "N3951-W7456.5/18 X 21.5 : 1982." Available also through the Library of Congress Web site as a raster image.
Geological Survey (U.S.); Pennsylvania. Bureau Of Topographic And Geologic Survey
1982
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