The Orange Line, is a rapid transit line in Chicago, Illinois run by the Chicago Transit Authority as part of the "L" system. It is about long and runs at grade and elevated on existing railroad embankments and new concrete and steel structures from Midway International Airport, the Southwest Side and downtown Chicago. In September 2012, the average weekday boardings on the Orange Line were 63,037. The Orange Line operates between Midway Airport and the Loop, weekdays from 4:00 a.m. to 1:25 a.m., and Saturdays and Sundays from 4:30 a.m. to 1:25 a.m.