>>924577When the CTA was formed, they inherited an order for PCC cars that they didn't really want but couldn't cancel. They also needed to modernize the "L" (which was still utilizing a large fleet of wooden cars at the time).
St. Louis Car Company had designed prototype rapid transit cars using the PCC technology (New York's "Bluebirds" and Chicago's 5000 Series) so the CTA scrapped their fleet within a few years of their arrival, and sent the parts back to be rebuilt into the 6000 Series.
