Tobin Bridge

The Maurice J. Tobin Memorial Bridge is a cantilever truss bridge that spans more than two miles from Boston to Chelsea over the Mystic River in Massachusetts. The bridge is the largest in New England. It is operated by the Massachusetts Department of Transportation and carries U.S. Route 1. It was built between 1948 and 1950 and opened to traffic on February 2, 1950, replacing the former Chelsea Street Bridge. The 36-foot wide roadway has three lanes of traffic on each of the two levels with Northbound traffic on the lower level and Southbound traffic on the upper level.
The bridge is a three-span cantilevered truss bridge at 1,525 ft in total length. The center span is longest at 800 ft and the maximum truss height is 115 ft . There are 36 approach spans to the North and 32 to the South. The roadway is seven lanes wide between the shortest span and the center to accommodate the now-unused toll plaza. The Northbound toll plaza was closed in the 1980s; the Southbound toll plaza was closed on July 21, 2014.

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