High Quality Content by WIKIPEDIA articles! The Harvard Bridge (also known locally as the MIT Bridge, the Massachusetts Avenue Bridge, and the "Mass. Ave." Bridge) is a steel haunched girder bridge between Back Bay, Boston to Cambridge, Massachusetts, USA, carrying Massachusetts Avenue (Route 2A) over the Charles River. It is the longest bridge over the Charles River at 659.82 meters (2,164.8 ft). It is locally known for being measured, inaccurately, in the idiosyncratic unit of length called the smoot.