On this day, October the 8th, in the year of 1871, the Great Chicago Fire, a fire which famously started at the O’Leary barn (legend having it as a cow kicking over a lantern, though the official cause remains unknown) and burned down an area around four miles in length and one mile wide, began.

Due to a mixture of Chicago’s rapid growth and lack of strict fire safety codes in place, a fire of this caliber wasn’t a stretch of the imagination. 

When firefighters and rain ended the blaze on October 10th, 300 lives were lost and 100,000 were left homeless.

Chicago would see vast economic, cultural, and population growth after the fire, shaping it into the city it is today (History) (Britannica).