The service suspension will begin at 10 p.m. Friday, Sept. 27, and run through 4 a.m. Monday, Oct. 7. Riders who want to travel between O’Hare International Airport and Rosemont, which means anyone going to or from the airport on the CTA, will need to take shuttle buses. Passengers at O’Hare can find the Bus Shuttle Center above the O’Hare Blue Line station between terminals 1, 2 and 3.