Harvard Bridge

Harvard Bridge
Harvard Bridge seen from Cambridge in August 2017
Coordinates42°21′16″N 71°05′29″W / 42.35457°N 71.09132°W / 42.35457; -71.09132
Carries Route 2A
CrossesCharles River
LocaleBostonCambridge, Massachusetts, United States
Maintained byMassDOT
ID numberB160124EYDOTNBI
Characteristics
DesignHaunched girder bridge
MaterialSteel
Total length2,164.8 ft (387.72 sm; 659.82 m) (roadway)
364.4 smoots ± one ear (620 m) (sidewalk from Storrow Drive to Cambridge only)
Width69.3 ft (12.42 sm; 21.13 m) (total width)
52 ft (9.3 sm; 15.8 m) (roadway)
No. of spans25
Piers in water24
Load limit86.4 short tons (78.4 t)
Clearance below12 ft (2.2 sm; 3.7 m)
History
Constructed byBoston Bridge Works
Construction start1887
Construction end1891
OpenedSeptember 1, 1891 (1891-09-01), 1990
Closed1983 (temporary closure for repairs)
Statistics
Daily traffic49,000 as of 2005
Location
Interactive map of Harvard Bridge

Harvard Bridge, also known locally as the Massachusetts Avenue Bridge and "Mass. Ave." Bridge, is a steel haunched girder bridge carrying Massachusetts Avenue (Route 2A) over the Charles River and connecting Back Bay, Boston with Cambridge, Massachusetts. At 2,164.8 feet (387.72 sm; 659.82 m), it is the longest bridge over the Charles River.

After years of disagreement between the cities of Boston and Cambridge, the bridge was built jointly by the two cities between 1887 and 1891. It is named for John Harvard, the founder of Harvard University. Originally equipped with a central swing span, it was revised several times over the years until its superstructure was completely replaced in the late 1980s due to unacceptable vibration and the collapse of a similar bridge in Connecticut.

The bridge is known locally for being marked off in the idiosyncratic unit of length called the smoot.