I found this photograph at my link page Dave's Electric Railroads, which is located
to the right of your computer screen at www.davesrailpix.com.
Before the Chicago Transit Authority began to color code their rapid transit lines in 1993, these
routes were known for many years by name. The names included the "Ravenswood Elevated" which is known today as the Brown Line, "The Lake Dan Ryan" line which is known today as the Green Line, and of course the "Douglas Park Elevated" line which is known today as the Pink line.
During the 1970's and 80's when this route was still refered to as the Douglas Park Elevated line, trains of the aging 1950's era 6000 Series rapid transit cars from the St. louis Car Company were assigned to this line. Many rolled out their last miles here during the 1980's, while "New" cars from the Boing Vertol Corp, practically made thir debut here during the late 1970's era.
No credit is given to the name of the photographer who had taken this photograph, but it appears to have been taken at some point during the early to mid 1970's era.
This two car /single unit married pair of 6000 series lightweight rapid transit cars, are viewed heading westbound past South Laramie Avenue in west suburban Cicero Illinois. This train is heading to the nearby west terminal at South 54th Avenue a few city blocks from here.
During the early to mid 1970's, two car single unit trains like this, were used during non rush hour / off peak travel hours over the CTA Douglas Park Elevated line. Today, two unit 4 car trains are the non rush hour standard on the Chicago Transit Authority's rapid transit lines.