[3] The Skokie Shops are equipped to perform comprehensive heavy maintenance on "L" trains, including collision repairs and mid-life overhauls.

Preparation work for the train takes approximately three months, supported by Skokie Shops staff and CTA employee volunteers.

Both the CRT and the CNS&M were partially controlled by businessman Samuel Insull, who led the consolidation of the entire Chicago "L" system in the early 1920s, and who also invested in utilities and property development throughout the region.

The CNS&M operated interurban service from Chicago to Milwaukee, and used the Skokie Valley Route as a high-speed bypass of its congested main line through downtown Evanston.

[6] The Chicago Transit Authority took over the operation of the "L" system from the CRT in 1947, and discontinued the local service on the Skokie Valley Route in 1948.

[8]: 9 Passenger service over the Skokie Valley Route resumed in April 1964 as a demonstration project, supported by federal funding.

An embankment collapsed at a Metropolitan Water Reclamation District facility east of the shops, damaging the Yellow Line tracks.