Greater Pittsburgh region, southwestern Pennsylvania; counties of Allegheny, Armstrong, Beaver, Butler, Washington, and Westmoreland, 1971

Scale 1:125,000; 1 in. equals approx. 2 miles; 1 cm. equals 1.25 km.
"Contour interval 100 feet."
"Lambert conformal conic projection."
"Compiled in 1971 from USGS quadrangles dated 1953-1969."
"50,000-foot grids based on Pennsylvania coordinate system, south and north zones."
"10,000 meter Universal Transverse Mercator grid ticks, zones 17."
Includes "Index to 1:24,000 scale quadrangle maps" and location map.
Available also through the Library of Congress Web site as a raster image.