1977 Chicago Loop derailment

The 1977 Chicago Loop derailment occurred on Friday February 4, 1977, when a Chicago Transit Authority elevated train rear-ended another on the northeast corner of the Chicago Loop at Wabash Avenue and Lake Street during the evening rush hour.
The collision forced the first four cars of the rear train off the elevated tracks, killing 11 people and injuring over 180 as the cars fell onto the street below.