About

Sanborn Fire Insurance Maps

Sanborn fire insurance maps are large scale historical city maps, detailed at the block and building level, that show residential, commercial, and industrial uses of sites, building footprints, potential environmental hazards, and construction details of structures. They show the size and shape of buildings, locations of windows and doors, and building materials as well as building use, street names, and property boundaries. The maps show urbanized or built-up areas of cities and were originally designed to assist fire insurance agents in determining the potential damage from fires, assessing risk, and setting premiums. Therefore, they also show information about direction of prevailing winds, water supply, and fire departments.

The Sanborn Map Company produced maps from the 1860s through to the present day, covering more than 12,000 cities and towns in North America. D.A. Sanborn, a Massachusetts surveyor, created an atlas of Boston and maps of several cities in Tennessee while working for insurance companies in the mid-1800s. In 1866, he founded the Sanborn Map Company in New York City. The Sanborn Map Company still produces maps and spatial data today. The historical Sanborn fire insurance maps were sold to Environmental Data Resources in 1996.

Much of the history of the Sanborn Map Company and the fire insurance maps given here comes from Fire Insurance Maps in the Library of Congress : Plans of North American Cities and Towns Produced by the Sanborn Map Company : a Checklist, compiled by the Reference and Bibliography Section, Geography and Map Division (1981) as excerpted by the University of California, Berkeley’s Earth Sciences and Map Library.

The Print Collection

In the late 1960s the Library of Congress transferred their duplicate copies of the Sanborn fire insurance maps acquired through copyright deposit. To the best of our knowledge, the University Libraries owns copies of all Sanborn fire insurance maps produced for Colorado, as they were originally printed^*. The collection maps approximately 560 cities, beginning in 1883 and ending in 1937.

The print collection may be viewed by appointment only. To read more about the Map Library’s print collection or to make an appointment, please visit the Map Library’s web pages.

^* The Sanborn Map Company issued updates and corrections to the maps in the form of paste-on slips. The Library of Congress collection did not contain any of the corrected maps; they only held maps in the form in which they were copyrighted. There are some cities for which the University of Colorado at Boulder Libraries did not receive original maps from the Library of Congress. Instead we purchased black and white photographic reproductions of those maps from the Library of Congress.

The Digital Collection

Building Colorado Story by Story: the Sanborn Fire Insurance Map Collection is a digital collection consisting of a portion of the Map Library’s print collection of Sanborn fire insurance maps. The University Libraries’ DIgitial Asset Library (DIAL) contains a total of 346 maps on 2,385 sheets. Building Colorado Story by Story contains maps of 79 principal cities in 52 counties covering the years 1883-1922.

Accessing the Maps
There are two ways to access the collection: the online interface or through the DIAL Luna Insight JVA Client. There are benefits to both interfaces. Through the online interface, the maps can be searched by choosing a city or county from a list or by selecting an area on a map. The Insight JVA Client does not support searching by map, but allows for downloads of high-resolution images of the maps. (The copyright to this collection is held by the Regents of the University of Colorado. Please abide by the conditions of use for any image you download from this collection.)

The Project

Building Colorado Story by Story: the Sanborn Fire Insurance Map Collection is a digital collection of Sanborn fire insurance maps made available through the University of Colorado Libraries’ Digital Asset Library (DIAL).

This project was made possible by a grant from the United States Institute of Museum and Library Services (IMLS) to the Colorado State Library (CSL) under the provisions of the Library Services and Technology Act (LSTA), through generous support from the University of Colorado Friends of the Libraries, and through the work of the faculty and staff of the University of Colorado Libraries and the Colorado Library Consortium (CLiC).

The project team has cataloged, scanned, created a geographically searchable interface for, and made available online 346 maps on 2,385 sheets, representing 79 principal cities in 52 counties covering the years of 1883-1922.

The Team

University of Colorado at Boulder
Kathryn Lage, Map Librarian (Principal Investigator)
Christopher Cronin, Head of Digital Resources Cataloging
Michael Dulock, Metadata Librarian
Holley Long, Digital Initiatives Librarian
Laura Wright, Library Technician III
Liz Bishoff, Special Assistant to the Dean and Head of Office of Sponsored Programs

Colorado Library Consortium (CLiC)
Beth Filar Williams, Regional Consultant

Geneva Mixon, Independent Consultant

Many thanks to Suzanne Larsen, Valerie Horton, Ilene Raynes, Naomi Heiser, Rick Losoff, and the Map Library's and Systems Department's student assistants for their hard work, advice, and support with this project.

The Scanning Process & the Digital Images

The University of Colorado at Boulder Libraries contracted with OCLC Preservation Services to scan the Sanborn fire insurance maps. The maps were scanned at 375 ppi and 24 bit color using a digital scan back. The digital images are archived as TIFFs. The images accessible through the Building Colorado Story by Story digital collection are JPEG2000s.

Cataloging & Metadata

MARC records for both the print and digitized maps are included in Chinook, the University of Colorado at Boulder Libraries’ catalog. The records are also included in Prospector (a unified library catalog for 23 libraries in Colorado and Wyoming), and OCLC’s WorldCat. The project team also plans to make the records available in the Colorado Virtual Library, and OAISTER, a union catalog of digital resources.

See the map cataloging page on the Accidental Map Librarian wiki for map cataloging tools and resources.