In the U.S. state of California, Interstate 80 (I-80), a major east–west route of the Interstate Highway System, has its western terminus (ending point) in San Francisco, California, United States. From there it heads east across the Bay Bridge to Oakland, where it turns north and crosses the Carquinez Bridge before turning back northeast through the Sacramento Valley. I-80 then goes northeast and east over the Sierra Nevada mountain range before crossing into the state of Nevada within the Truckee (River) Canyon. The speed limit is 65mph instead of the state's maximum of 70mph since the road passes exclusively through urban and mountainous areas in California.Interstate 80 has portions designated as the Eastshore Freeway and Alan S. Hart Freeway.Route descriptionI-80 is recognized as the Dwight D. Eisenhower Highway and a Blue Star Memorial Highway for its entire length. It was part of the Lincoln Highway from Sacramento to Reno (except in vicinity of Donner Summit). I-80 is also known as the Kent D. Pursel Memorial Freeway from the Bay Bridge to the Alameda/Contra Costa County line (named after a former Alameda County Board of Supervisor), the Linus F. Claeys Freeway from SR 4 to the Carquinez Bridge (after a Contra Costa County businessman and philanthropist), the Alan S. Hart Freeway from the Sacramento/Placer County line to the Nevada state line (named after a Caltrans engineer who oversaw the modernization of this segment of I-80), and the Dutch Flat and Donner Lake Wagon Road from Emigrant Gap to Donner Lake (except in vicinity of Donner Summit).