The "L" also referred to as "El" is a rapid transit system serving the city of Chicago and its surrounding suburbs. This transit system is operated by Chicago Transit Authority, second largest rapid transit system in United States.

Operations of the oldest section of "L" started sometime in 1892. At present "L" consists of eight rapid lines laid out in a spoke hub distribution paradigm focusing transit towards a central loop. Since then this rapid transit system has been catering to hundreds and thousands of people.

On an average the "L" provides comfortable ride to over 658,524 people every week and this number reaches 419,258 on Saturday and nearly 315,240 on Sunday's. Chicago Subways remained on the planning board for two and a half decades until funding was available in mid 1930's.

The first passenger subway line in the world, the Metropolitan Railway was opened in 1863. Since then subways were built in number of other cities including Paris, New York and Boston.

Construction of two subway lines in Chicago was taken up in the year 1939 and was completed by 1943. Although more subways were planned, they were not taken up any further immediately since other solutions like placing rapid transit lines in expressway medians proved to be cost effective.

Clinton station featuring amazing amenities was opened in 1958. The amenities provided by this station include concession stand, public toilets, telephones, lockers, agent booths and fare counters at its corners.

Each of these stations used one color on accent trim and inlaid signage throughout the platform. Apart from the station names on the wall, number of different backlit signs directed passengers towards escalators and other necessities.