|undated postcard of PCC cars in Newton, one of Boston's suburbs|
The Boston transit system has operated PCC cars continuously since the initial demonstrator was delivered in 1937 and is the only transit system in North America to have kept the cars on their active roster since the PCC design was developed.
The remaining line using these cars is the Mattapan-Ashmont high speed trolley line, built in 1928 along a former steam railroad right-of-way as an extension of the Cambridge-Dorchester (now "Red") rapid transit line. The line has used PCC cars since the 1950s and the cars now serving the line were extensively rebuilt in the last decade. They are the only remaining PCC cars built by Worcester, Mass.-based Pullman-Standard and the only air-electric PCCs still in service.
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