100 W. Jefferson St.

Historical marker location:

100 W Jefferson St, Ottawa, Illinois

( Marker is at the intersection of Columbus Street (Illinois Route 23) and West Jefferson Street, on the left when traveling north on Columbus Street.)

The Great Chicago Fire of 1871 was one of the most devastating fires in U.S. history. The fire destroyed much of the city, including over 17,000 buildings and left more than 100,000 people homeless. The fire started in a barn owned by Patrick and Catherine O'Leary, but the cause of the fire is still debated to this day.