Each map covers 9 counties in southwestern Pennsylvania. "June 1989." Panel title. Maps numbered: 956-40021-DSC-June 89 [thru] 956-40028-DSC-June 89. Each map has a separate index. Text, large map titled "Our region helped build America, now we want to share the heritage with you," location map, ill., and blank panel on verso. On recto: NPS D-2. On verso: 956-40020-DSC-June 89. Available also through the Library of Congress Web site as a raster image.
United States. National Park Service; America'S Industrial Heritage Project
1989
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