- Locale
- Chicago , Illinois , and suburbs, United States
- Transit type
- Rapid transit
- Line number
- Blue Line Brown Line Green Line Orange Line Pink Line Purple Line Red Line Yellow Line
- Daily ridership
- 385,500 (weekdays, Q1 2026)
- Annual ridership
- 135,202,800 (2025)
- Chief executive
- Nora Leerhsen
- Headquarters
- 567 West Lake Street, Chicago, Illinois
- Website
- www .transitchicago .com
- Began operation
- June 6, 1892 ; 133 years ago ( 1892-06-06 )
- Operator s
- Chicago Transit Authority
- System length
- 102.8 mi (165.4 km)
- Track gauge
- 4 ft 8 + 1 ⁄ 2 in ( 1,435 mm ) standard gauge
- Minimum radius of curvature
- 90 feet (27.432 m)
- Electrification
- Third rail , 600 V DC
- Top speed
- 55 mph (90 km/h)