Final answer:
The Great Chicago Fire started in a barn owned by the O'Leary family on DeKoven Street in 1871.
Step-by-step explanation:
The Great Chicago Fire started on October 8, 1871, in a barn owned by the O'Leary family on DeKoven Street. The fire quickly spread, fueled by strong winds, and burned for two days, destroying a large portion of the city. Today, the spot where the fire started is located in the West Side of Chicago.
Learn more about The Great Chicago Fire