Seeing Philadelphia’s Past in Augmented Reality



Guest article by Deborah Boyer and Andrew Thompson.

For over 140 years, the City of Philadelphia has been taking pictures of itself.  Though local pride is never in short supply in Philly, far more practical reasons like risk management and documentation of public works projects have motivated decades of city-employed photographers to capture images of streets, buildings, and events in all corners of the city.  The Philadelphia City Archives, under the administration of the City of Philadelphia’s Department of Records (DOR), is now tasked with maintaining the collection and serves as the resting place for an estimated 2 million photographs, an invaluable source of insight into the City’s rich history.

Accessing the images, however, was a difficult process.  Individuals had to travel to the City Archives during open hours, page through an index, and submit requests for certain photographs – and even then much of the photo collection was not fully catalogued.  Only a few hundred people completed the process each year.

Those who did found a unique collection: a century of snapshots, many with a geographic element. Most of the images are of a specific location identified by the original photographer, information that can be important both to a scholar researching the history of a developing neighborhood and a history enthusiast looking at her old elementary school.  The potential for the DOR’s collection of images to inspire local historical research, education, and old-fashioned awe was incredible.

In the early 2000s, the DOR began searching for a method to provide easier access to the photos by digitizing and placing them online.  The DOR partnered with Azavea ( a local software company specializing in Geographic Information Systems (GIS), and in 2005, the team launched (, a web-based digital asset management system that provides online access to the digitized images.  Users can search through the collection by geographic location, keyword, date, and other criteria.  In addition, each image in the system is also accompanied by a map of the location where the photo was taken and a link to view that location as it looks today via Google Street View.  Administrators can also use to manage and update the photo collections.

The map-based search page emphasizes the geographic information available for many of the images.

The map-based search page emphasizes the geographic information available for many of the images.

Over the past six years, what started as a simple website with only 90 images from the City Archives has developed into an online database with over 95,000 historic photographs and maps from five Philadelphia organizations.  Currently, has over 7,300 registered users and regularly receives over 13,000 unique visitors per month.  Map- and address-based searches have consistently been the most frequently used on, with over 682,000 address searches performed in the last year compared to only 160,000 keyword searches.  Users also often provide positive feedback related to the unique geographic features of

“Thank You for all this amazing work you are doing to keep the history of Philadelphia alive so future generations will see what a truly great city this is. I was born there and feel it’s still my city even though I live 3,000 miles away. I am so proud of what I find here and enjoy it so much! Thank you again for all your hard work and dedication to this project. You are making a lot of folks happy!” User

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