Chicago's rapid transit system, most commonly referred to as the "L" (short for "elevated train"), serves around 650,000 passengers on an average weekday, making it the 3rd busiest rapid transit system in the U.S., behind only the New York subway and the Washington D.C. Metro.
Currently, the Chicago "L" system encompasses 145 different stations, and runs over eight individual lines (Red, Blue, Orange, Green, Brown, Yellow, Purple, and Pink), of which none are more frequently used than the lakefront Red Line. But despite the Red Line being the city's most frequently used railway however, it's the Clark/Lake station in the Loop, which isn't a part of the CTA's Red Line, that routinely sees the most traffic, with an average of 20,765 passengers passing
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