57
The 57 Watertown Yard-Kenmore Station route is the replacement for the Green Line "A" Branch service which was discontinued in 1969. Route 57 was formerly one of the few routes that ran limited-stop service in the Boston city limits (no pickups were made on Commonwealth Avenue between Packard's Corner and Kenmore), but this practice was discontinued in December 2006.
Read more about this topic: List Of Key MBTA Bus Routes, Route List