http://world.nycsubway.org/us/chicago/green.html World.nycsubway.org – Chicago Green Line] It utilizes the system's oldest segments (dating back to 1892), extending 20 miles 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 West Englewood (Ashland/63rd) and Woodlawn (Cottage Grove/63rd).