"L" System History | Chronologies

"L" System History

The Chicago "L" system is a unification of lines built and formerly operated by competing companies. The companies were fully unified in 1924, though the operations of the previous companies were maintained as divisions of the united unit. In 1947, the system went public and underwent many changes before taking on its present form. Look inside these main categories for construction history, a description of each transit line line, future plans, and more.

The History and Chronologies section is currently undergoing major renovations. We are working to provide expanded and more complete historical narratives, better graphics, and links to related material elsewhere on the site. The post-World War II history of the elevated has been updated and the chronologies have been modified. The prewar histories will be expanded in the near future.



The Early Years: (1888-1913)
The Original "L" Lines

Unification and the Subways: (1913-1947)
The CER and CRT Centralize "L" Operations

The North Shore Line and the "L"
The Subways

The CTA is Created: (1947)
A New Era Begins

The CTA Takes Over: (1947-1970)
Resurrection Through Modernization

The System Contracts as the Fleet Modernizes
Chicago Pioneers the Median Transit Line
The Skokie Line Returns
Return to the Median: The Dan Ryan Line and the Milwaukee/Kennedy Extension

Chicago Goes Regional: (1974)
The RTA is Created

CTA in the Auto Age: (1974-1990)
Subsidies and Line Grow, Ridership Falls

The RTA Falters and the CTA Struggles
New Cars and Line Extensions...
...But the CTA Continues Its Downward Spiral

The CTA Reinvents Itself: (1990-present)
The "L" Heading Into the 21st Century

Through-Routes Realigned
"L" To The Southwest Side: A New Way to Midway
Green Line Closes For Rehabilitation
Booz-Allen Hamilton Service Cuts
CTA in the 21st Century



The chronologies present the history of the "L" in a simple date-by-date fashion, broken down between the four original operating elevated companies, the Chicago Rapid Transit, and the Chicago Transit Authority. The major events and changes in the system's history are listed in chronological order, with brief descriptions.