Relief shown by contours and spot heights. Panel title. "Compiled by the D.C. Department of Corrections, Lorton, Virginia, under the technical direction of the National Mapping Division, USGS, from 1976 aerial photographs. Revised and field checked by USGS 1983. Map edited 1979 and 1984." "1979." "Projection and 100-meter grid: Universal transverse Mercator, zone 18." Includes ancillary map of "Routes to the National Center." Text, diagram of "Rock Garden Walk," geologic map and cross-section of site, and col. ill. on verso. Available also through the Library of Congress Web site as a raster image.
Geological Survey (U.S.)
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