A quirky bit of the T is the High speed trolley line from Ashmont to Mattapan with 70 year old PCC cars. Intended as a "trolley freeway" now lives on as a link to Ashmont from Mattapan.
Type 7 built by Kinki Sharyo has been the most reliable trolley since the PCC serving Boston from the mid 1980's. This bit of the E branch is in the street but may change in the future.
Type 8 trolley built by Breda is rolling through a bit of the T that is a throwback to the trolley era rolling in mixed traffic. Plans being considered may alter this view in the future.
A set of 01600 cars built in 1970 cross the peak of the Longfellow Bridge. These are due to retirement as the new CRRC cars come on line. This bridge was recently rebuilt in the last years.