A Type 7 arrives in Park Street via the oldest Subway in the USA. Unique feature of Park Street on the inbound side is a track right in the middle of the platform you can walk across.
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.