From the Pittsburgh Post-Gazette:
Pittsburgh Mapping and Historical Site Viewer” — http://peoplemaps.esri.com/pittviewer/ — popped up on someone’s Facebook page, then spread. Jonathon Denson of McKees Rocks described it as “an awesome mapping tool” on his Discovering Historic Pittsburgh website. Someone then posted it on City-Data.com, where Gene Wilson of Allegheny West found it.
To create the viewer, [site developer] Mr. [Chris] Olsen [a member of the ESRI tech support team] downloaded and scanned the historic plat maps of the years that were available and spliced them to create one map of Pittsburgh and Allegheny City in eight overlays. The user can zoom in and use a time line to see overlays for 1835, 1855, 1872, 1882, 1903-07, 1910, 1923 and 2010, an aerial view.
Symbols on the map are links to information boxes, usually with a photo, about historic sites.
“I am a big fan of history and looking at historical maps was always fun for me,” said Mr. Olsen, who credited the ArcGIS software for doing the hard part. “When I stumbled across the [Pitt] site, I thought, ‘This is great,’ but you had to go to different plats. They were organized well, but the challenge was to get them to all fit together.”
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