Guides to house number and streetname changes
from the Chicago History Museum
Guide to 1909 house number changes outside downtown (170MB PDF)
Guide to 1911 house number changes downtown (47MB PDF)
Guide to streetname changes (small PDF)

The online Encyclopedia of Chicago
includes maps from the published book and other maps
from the Chicago History Museum

University of Chicago map library
online digital collection

David Rumsey map collection
enormous online collection of historic maps

Library of Congress Images of America
primarily 19th century birds-eye views

Harvard University map library
online digital collection

University of Alabama
collection of national atlas maps of Chicago

NOAA Coast Survey historic charts
collection of coastal charts, including the Lake Michigan coastline

Texas A&M University
1902 Geologic Atlas folio of Chicago area

Chicago Public Library
Sanborns Fire Insurance Maps online
click here for a guide to volume numbers

Historic Chicago transit maps
at Chicago-L.org

Smoke Abatement maps of Chicago railroads & industry
download full 1915 report (1177 pages) in PDF format from archive.org
download 151 map pages only in PDF format

Chicago Land Use Survey
Vol. I: Residential Chicago
Vol. II: Land Use in Chicago
full 1942 reports in PDF format from archive.org

Aerial photos of Cook County 1938
download from Illinois State Geological Survey (MrSID format)

Historic aerial photos
from HistoricAerials.com

Jazz Age Chicago maps
maps of Chicago’s bright-lights districts in the 1920s

Original surveyors maps and notes for Cook County
before European settlement