Retrographer (Pittsburgh) - Retrographer harnesses the knowledge of the community to create a collaborative map of Pittsburgh’s historic photographs. All of the photographs on the site come from the City Photographer collection hosted and curated by the University of Pittsburgh’s Archives Services Center. Retrographer uses Google Maps to make it easy for anybody to geotag these images. This geotag data is sent back to the Archives Services Center to become a permanent part of the archive. Retrographer is looking to expand to other cities as well. As you can see, the above is the well known corner of Forbes and S. Craig.