A Window to the Past and a
Tool for the Future
Talk Outline
I. What are Sanborn Maps?
II. History of Sanborn Company
III. Details about the Sanborn Maps
IV. Uses of the Sanborn Maps
V. Understanding the Maps
VI. CU’s Collection
VII. Accessing CU’s Collection
I. What are Sanborn Maps?
Sanborn Maps
Fire Insurance Maps
Large Scale
Detailed (50 feet to 1 inch)
Date Back to the 1860s
Updated Regularly Until 1950s
London was prone to fires throughout its history
Detail of painting from 1666 of the Great Fire of London by an
unknown artist. Photo taken from Wikipedia
Fire Insurance
emerged in
London in the
late 1700s
•The American Insurance Industry spurred
the growth of mapping companies in the late
•Mapping companies supplied information to
insurance underwriters.
II. The History of the Sanborn Maps
Insurance underwriters were interested in
basing their rates according to the relative
risk of fires in the commercial districts of
American cities.
Daniel A. Sanborn
founded the Sanborn
National Insurance
Diagram Bureau in New
York City after
successfully surveying
Portrait of Daniel A. Sanborn
Adopted the Name “Sanborn Map
Company” in 1902 and Eventually Emerged
as the Leader in the Field
The Sanborn Company’s success was due to
•Absorption of other companies
•Richly detailed and comprehensive maps
•Highly accurate
•Good management practices
•Standardized symbolization
Published a system of standards for accuracy in
At Sanborn’s peak (1920s):
•employed surveyors in every state
•held a virtual monopoly
-Worked anonymously
-Names never appeared on maps
-Surveyors occasionally gained notoriety
or celebrity after leaving the Company
Daniel Carter Beard
From: Wikipedia
“While working for them I not only saw all
those places I had heard about but I made
maps of them, made diagrams of all the
homes in each town and city I visited. I
took delight in putting into my records
mention of real occupancy, genteel or
disreputable. After four or five years of this
work I knew a lot about our people, saints
and sinners, rich and poor.”
Dan Beard, Hardly a Man Is Now Alive, the
Autobiography of Dan Beard (New York, 1939), p.
III. Details About the Sanborn Maps
Most Sanborn maps were drawn at a scale
of 50 feet to 1 inch until after WW II
Quickbird Satellite Image
Maps focus on urban areas
“Map of Congested District of Salt Lake City Utah” 1911
The Sanborn Mapping Company (Scale 200ft to 1in)
Maps Include:
Details regarding
the size, shape,
and construction of
dwellings, and
Paonia Colorado circa 1908
Maps Include:
Not just location but the composition of
all buildings within a city or town
Wood Frame
Stone Building
Fireproof Building
Wood Frame w/
Iron Facade
Maps Include:
Noted strength of fire department and
sometimes the number of engines or
firefighters at each station
Maps Include:
Location of water
and gas mains as
well as things like
hydrants, and
Maps Include:
Labels on most public buildings:
From landmarks to brothels
(“Female Boarding”, “FB”, “Ill Fame”, “Bagnios” etc.)
Reno, NV
Maps Include:
Street names, railroad lines, and
Indian Reservations
Some maps may
about prevailing
winds and
Sanborn Company resurveyed quickly
after a disaster to note the buildings that
had survived or been lost.
For Example it took less than one week
following the Chicago Stockyard fire of
1934 to produce updated map
Chicago Stockyards 1947
Thematic Map of Chicago Stockyard Produced
by the Sanborn Company (date unknown)
Corrections and Updates:
In 1930 Sanborn
Co. began to
allow correction
The Decline of the Fire Insurance Maps:
•The maps were costly
•1929 stock market crash and depression
•During WWII government placed restrictions on
map production and building construction
•Difficulty keeping pace with the post WWII
population and development boom
By the 1960s the insurance industry shifted
away from using maps to assess risk
IV. Uses of the Sanborn Maps
Urban Morphology
Studies the physical form of a city including
• street patterns
• buildings sizes and shapes
• architecture
• population density
• patterns of land uses
How does physical form produce or
reproduce social forms?
Urban Morphology
Dr. Vaselka used Sanborn maps to examine
how the the design and placement of
courthouse squares in Texas affected sense
of community.
Quickbird Satellite Image of
Denton, TX
“Courthouse on the Square”
The development of the Barrio Libre
Neighborhood, Tuscon
Historical Sociology
Studies the past to find out how societies
work and change
Photo from
Example: Washington DC “alley life”
Alley Dwellings
After the Civil War small dwellings were built in the allies
that ran between many city blocks in D.C.
The most common residents of these allies were poor or
African American.
Public perception of allies and inhabitants:
crime ridden
rampant immorality and disease
Louse Alley
Investigations into these “red light districts” were
conducted in the early 1900s.
Louse alley was considered one of the worst offenders.
View of Louse Alley published in Charles
Weller's 1909 expose Neglected Neighbors.
Louse Alley
“Bawdy houses” and “alley dwellings” were abolished during early
twentieth century Reform Movements
Louse Alley, then renamed Armory Place, was reconfigured as a
minor street.
Armory Place was demolished in the 1930s as an attempt to
further rid the city of “alley dwellings” and as part of a
“beautification” campaign
Temporary housing was erected after WWII and for a time part of
the area was used as dedicated open space.
Louse Alley
Currently the American Indian Museum stands on part
of the site of Louse Alley.
Before the Museum was built intensive archeological
investigations of Lots 11 and 12 of Louse Alley were
conducted in Reservation C
Louse Alley
-Mary Anne Hall’s
Brothel (Lot 12)
- Adjacent parcel
theorized to be a
trash dump for the
brothel and location
of a boarding house
(Lot 11)
Corks, foil and wire
from champagne
Fine pottery
Louse Alley
Sanborn maps
guided the
excavation and are
one of the few
records of both
“alley life” and
“alley dwellers”
Louse Alley
All references and photos used were taken
from the Smithsonian Institute:
As evident from the
Louse Alley example the
Sanborn maps
frequently aid
From Footprint of a Sawmill:Archeological Investigation Into the Nurre
Sawmill in Williamsburg, KY (by Grant, Keit, and Mauck)
Historic Preservation
“The process of preserving part of a community, from an
individual building or part of a building to a whole
neighborhood (including roadways and waterways), because
of its historical importance.” (from
Taos square in historic Georgetown awaits restoration
Historic Preservation
Since the maps contain
such rich details regarding
the size, shape, and
construction of commercial
buildings, dwellings, and
structures they are an
excellent resource for
historic preservation.
The study or investigation of
ancestry and family history.
Campbell of Glenorchy Family Tree
George Jamesone, 1635.
Scottish National Portrait Gallery
Sanborn’s generally do not contain family
names so they are often used when the
address of an ancestor is known.
Since the Sanborn maps only cover urban
areas they are best for research city dwelling
Treasure Hunting
Bottle hunters and individuals who use metal
detectors to find treasure often use the Sanborn
maps to locate privy or outhouse sites.
Compliments of “Digger” from “
V. Understanding the Maps
Understanding Sanborn Maps
Sanborn maps contain a rich amount of
information and detail
In order to understand and interpret the maps
you must make use of a complex legend
VI. CU’s Collection
CU’s Complete Collection
•Largest collection of Colorado Sanborn
maps outside of the Library of Congress
•Presented as a gift by the Library of
Congress in the late 1960s
•The collection includes over 567 color maps
produced between 1883 – 1931
CU’s Complete Collection
The holdings include a nearly complete
collection of what was mapped in Colorado
More mapping was conducted in regions that
were more populated or had significant
mining activity in the late 19th and early 20th
* Leadville’s peak number of map sheets
date from the late 1800s
The collection also includes some “ghost
Accessing Paper Maps
Maps can be accesses from 9-5 M-F
Jerry Crail Johnson Earth Sciences and Map
Contact the library staff in advance
Via email: [email protected]
Via phone: 303-492-7578
Accessing Paper Maps (Cont’d)
•Sanborn maps do not circulate
•Cannot photocopy the maps
•Digital photographs are permitted
•Some maps are also available on microfiche*
and can be printed out
Scanned collection includes:
• 346 maps on 2,385 sheets,
• 79 cities
• 52 counties
• spans 1883-1922
VII. Accessing CU’s Digital
A Quick overview of CU’s interface
Digital Collection can be accessed at