Guide map of Chicago, October 11th, 1871

America Transformed: By 1870, Chicago's population approached 300,000, making it the nation's fifth largest city. This guide map, published just after the Great Chicago Fire, superimposes the burned area over the gridded street pattern. The fire started southwest of the city center and burned over 2,000 acres, noted by the shaded red area. A strong southwest wind, wooden structures, and summer drought fueled the flames that left approximately 100,000 people homeless. Though legend suggests that a cow caused the flames by knocking over a lantern, the real cause is unknown. In reaction to the mass destruction, city officials and urban planners lobbied for stricter building codes and better fire-fighting services.
Courtesy of Boston Public Library