A newly revised version of the historic USGS 15 minute topographic maps for Pennsylvania as collected from the MapTech Historical Map Collection at 'http://historical.maptech.com'. As an improvement to the initial version, the original scanned images from MapTech were downloaded, assembled with mosaicing software, and georeferenced to the statewide Albers NAD83 projection. Historic USGS 15 minute topographic maps for Pennsylvania as collected from the MapTech Historical Map Collection at 'http://historical.maptech.com'. Scanned map images from MapTech were downloaded, assembled, and registered and rectified via Arc/Info to a custom Albers NAD83 projection. The name of the map file will tell you the 15 minute quadrangle, the two letter abbreviation of the state is mostly in and the year it references. Another key point to remember is that through the decades some of the 15 minute USGS quads have changed names. Some examples include the following groups: (Alburtis-Allentown West-Slatington), (Dingmans Ferry-Wallpack), and (Lehighton-Mauch Chunk). On most average monitors the maps look best at a scale of 1:25,000 to 1:30,000.