Carquinez Bridge
Suspension and cantilever bridges on San Pablo Bay
The Carquinez Bridge is a pair of parallel bridges spanning the Carquinez Strait at the northeastern end of San Francisco Bay. They form the part of Interstate 80 between Crockett and Vallejo, California, United States.
The name Carquinez Bridge originally referred to a single cantilever bridge built in 1927, which was part of the direct route between San Francisco and Sacramento. A second parallel cantilever bridge was completed in 1958 to deal with the increased traffic.
Later, seismic problems made the 1927 span unsafe in case of an earthquake, and led to the construction, and 2003 opening, of a replacement: a suspension bridge officially named the Alfred Zampa Memorial Bridge, in memory of iron worker Al Zampa, who played an integral role in the construction of numerous San Francisco Bay Area bridges. The Alfred Zampa Memorial Bridge carries southbound traffic from Vallejo to Crockett, and the 1958 cantilever span carries northbound traffic.
History and description
The first regular crossing of the Carquinez Strait began in the mid-1800s as a ferry operated between the cities of Benicia and Martinez, six miles upstream from the bridge site. Auto service started on this route in 1913. A train ferry operated between Benicia and Port Costa from 1879 until 1930 when a rail bridge opened. Ferry service at the site of the bridge started in 1913 by the Rodeo-Vallejo Ferry Company.
Begin with the source’s own compact description: “Carquinez Bridge” is suspension and cantilever bridges on San Pablo Bay. The dossier treats that line as a proposition to test through Carquinez, Bridge and Suspension, not as a finished interpretation.
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The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Sep 10, 2026. The linked authority identifier is Q1044833. Authority coordinates are 38.061, -122.226. 2 of 2 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1927, 1958, 2003 and 1913.
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This entry incorporates text from “Carquinez Bridge” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.