California 37 east reassurance shield is posted near Sears Point east of Novato. Photo taken 11/26/04.
California 37 is a major route connecting the cities of the North Bay. Starting at U.S. 101 in Novato, California 37 carries two to four lanes across the marshy flats that define the northern shore of the San Francisco (San Pablo) Bay. The highway intersects California 121 at Sears Point, then swings southeast into Vallejo. Passing to the north of that city, California 37 again changes into a expressway/freeway combination as it connects with California 29 and Interstate 80.
With a spate of accidents and injuries in the 1990s, California 37 carried the inglorious moniker "Blood Alley," resulting in a higher priority for local politicians to find funding to make California 37 into an expressway and ultimately as a freeway. Currently, sections of California 37 slated for such an expansion, especially in Vallejo, where a new interchange is planned with California 29. The stretch along the marshy north shore is also slated for expansion, but such work requires extensive environmental review due to the preponderance of wetlands in the vicinity.
Historically, California 37 was more of a north-south route than east-west route. It used to follow the path now taken by California 121, coming to its northern terminus at California 128 near Lake Berryessa. California 48 covered the stretch of California 37 from Sears Point east to Vallejo. However, in an effort to streamline the north shore corridor with one number, California 37 was rerouted onto former California 48, and it became more of an east-west rather than north-south route. The California 48 designation was transferred to a proposed east-west freeway in the Antelope Valley near Lancaster/Palmdale; the freeway has not yet been constructed.
California 37 Highway Guides
Page Updated November 29, 2011.