WLS-TV Chicago, IL 2/20/18:
CTA color-coded lines celebrate 25 years
CHICAGO (WLS) --The Chicago L celebrates 25 years of color-coded rail lines Wednesday. In 1993, CTA debuted its red, blue, brown, purple, green and yellow lines to make life simpler."The color being the name could be carried... through visual motifs on the signs, on the trains, and in the stations," explained Graham Garfield, the CTA's General Manager of Customer Information and unofficial historian.
As vintage CTA maps will show, train lines "were either directional like north-south route," or referenced local neighborhoods, he added.
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