On October 8, 1871, a fire started in or around Mrs. Kate O'Leary's barn on 37 DeKoven Street on Chicago's West Side and over the course of the next three days wiped out most of the rollicking business district of the city by the Lake. 300 Chicagoans died, 90,000 lost their homes, and the property loss was $200 million.
Here is the site where the fire started.
Here are some questions answered about the Chicago Fire - particularly whether Daisy did it or not?
Or maybe comets did it?
Here is an eye-witness account published in the Chicago Tribune on October 14, 1871.
Here is a kid's site about the Fire that has cute illustrations that I like.
And here is the Chicago Historical Society doing what it does.
Best of all, is this book from the Library of Congress' archive of 19th century books in print entitled, "Chicago and the Great Conflagration" by Ellias Colbert and Everett Chamberlin. With numerous illustrations by Chapin & Gulick, from photographic views taken on the spot! God bless L.O.C.