Questions? Comments? Reach out to us at agsl@uwm.edu.
The Sanborn Maps of Milwaukee are fire insurance atlases held by the American Geographical Society Library (AGSL). The 1910 atlas includes eight volumes, consisting of 830 map sheets. The 1894 atlas includes four volumes, consisting of 450 map sheets. Sanborn maps were designed to assist fire insurance agents with insuring property. Produced for over 12,000 urbanized areas in the United States, Sanborn maps have been described by the Library of Congress as "the single most important record of urban growth and development in the United States during the past one hundred years." The American Geographical Society Library holds Sanborn maps dating back to 1894.
In their original format, the 830 sheets are 25 inches tall by 22.5 inches wide. Each sheet exists as an individual map item, and a particular city block can be found by referencing a paper key. The maps were digitized and uploaded to the library’s Digital Collections in 2007. To find an area, one must reference a digitized map key.
Finding information in these incredibly detailed and valuable map sheets is hindered by the segmented viewing process of having to cross-reference map sheets with keys. This process of navigating thumbnails in a digital collection does not lend itself to a truly immersive experience, where one can get a feel for what the city was like at the time, or conceptualize how one map sheet fits in with others. For that reason, the American Geographical Society Library identified this project as a goal for the library.
In 2017, the Milwaukee County Land Information Office (MCLIO) georeferenced the American Geographical Society’s 1910 Sanborn atlas sheets. Adding geographic location to these library items has opened doors for many exciting ways that scholars can access historic information from these sources. Now, the sheets appear as one seamless map, but each sheet can be isolated and linked to the individual item in the digital collection. This project is one of many the AGSL is envisioning for these resources, so stay tuned for more to come.
In 2018, the MCLIO georeferenced the entire 1894 set. As of 2022, the MCLIO is preparing to georeference the 1927 volumes held by the AGSL which are due to enter the public domain in 2023.
Have an idea for a mapping project using this atlas? The mosaiced sheets are published and available as map services:
The application was built using Leaflet, a light-weight, flexible Javascript library created for web mapping.
Belle Lipton: Designer / Developer - About Belle
Lauren Winkler: Designer / Developer - About Lauren
Bob Cowling: Updated application in 2020 - About Bob
Continued maintenance by Stephen Appel - About Stephen
Marker based on a design created by Alex Kwa from the Noun Project
Stephen Appel – Geospatial Information Librarian, American Geographical Society Library
Chris Scheele – Department of Geography, University of Wisconsin Madison
Emily Berth – GIS Technician, Milwaukee County Land Information Office
Kurt Meigast – IT Manager, UWM School of Architecture and Urban Planning