
Commuter rail (also known as "regional rail") connects communities by rail across metropolitan areas. Commuter railways generally connect cities and suburbs in a regional network.
A good example of a commuter rail system is Metra, which serves the greater Chicago area within northeastern Illinois (and to Kenosha, WI) along 11 major rail routes, with both local and express services. Metra carries hundreds of thousands of passengers on an average weekday and benefits both the suburbs and suburban cities it serves as well as downtown Chicago by connecting people, communities and jobs.
Metra is the consolidated set of commuter railway services formerly provided by historic railways such as The Chicago and North Western, The Milwaukee Road, The Burlington, The Illinois Central, and The Rock Island Line.
While Metra's system is largely a hub-and-spoke model today (as a result of the legacy of different railroads providing service to downtown Chicago from wherever their respective mainline railroads went), many cities are moving to make their networks more interconnected, such as the proposed Metra STAR Line, which would provide transit between suburbs without a need to travel downtown and then back out for suburb-to-suburb transit.