Consolidation
In 1913 Chicago's four elevated railroad companies came together to form the Chicago Elevated Railways Collateral Trust establishing crosstown services for the first time, and in 1924 all four companies were formally united to form the Chicago Rapid Transit Company. The Chicago Transit Authority took over the assets of the CRT in 1947. The Normal Park branch closed in 1954 and the Kenwood and Stock Yards branches were abandoned in 1957 but most of the rest of the route of the South Side Elevated Railroad continues in service as part of the CTA's Green Line.
Read more about this topic: South Side Elevated Railroad