From Fort Wayne Junction (21st Street), the IC line turns southwest, with the elevated CTA Orange Line (to Midway Airport) alongside to the southeast, with 4MT, CTC, speed limit 30-25, past a bridge over West Cermak Road, a bridge over South Canal Street, with their intersection just to the west of the line, Archer Avenue alongside to the south side of the Orange Line, a curve west-southwest (speed limit 25 mph), three Interstate Highway bridges overhead (I-90/94), Halsted Street (MP 2.6), where the speed limit is 25 mph through the curves back to the southwest, a bridge over South Halsted Street, the CTA Halsted station on the Orange Line a bridge over South Corbett Street, a bridge over South Senour Avenue, a bridge over South Mary Street, a bridge over South Stark Street, a bridge over South Throop Street, South Grove Street alongside to the northwest, a bridge over South Bonfield Street, a bridge over South Loomis Street, a through truss bridge over West Fuller Street, and a bridge over South Lock Street, with I-55 alongside to the southeast.
The Orange Line is built on the right-of-way once used by the Santa Fe, so trains headed for the Santa Fe line west of Bridgeport now run on the IC between 21st Street and Bridgeport. There is a CTA station on the Orange Line at Ashland Avenue, a bridge over Ashland Avenue, and the east end of the IC Bridgeport Yard on the northwest side of the line, at Bridgeport (MP 3.5), where, the IC tracks fork, with the former GM&O, former Alton line turning southwest, and the IC line west to Iowa turning due west, with two Santa Fe tracks now alongside it to the south, operated as Four Main Tracks from this point west.