Green Line (CTA)

The Green Line is a rapid transit line on the Chicago Transit Authority's "L" system. It is the only completely elevated route in the entire system. It utilizes the system's oldest segments (dating back to 1892), extending with 30 stops between Forest Park and Oak Park (Harlem/Lake), through Chicago's West Side to the Loop, and then to the South Side and Englewood (Ashland/63rd) and Woodlawn (Cottage Grove/63rd). 
As of September 2012, the average number weekday boardings on the Green Line is 70,554. The Green Line operates between Harlem/Lake and Cottage Grove, weekdays from 4:00 a.m. to 1:00 a.m., and Saturdays and Sundays from 5:00 a.m. to 1:00 a.m., and between Harlem/Lake and Ashland/63rd, weekdays from 3:50 a.m. to 1:05 a.m., and Saturdays and Sundays from 4:50 a.m. to 1:05 a.m.