The most populous cities in area code 510 are: San Jose, San Francisco, Oakland, Fremont, and Hayward.
Other cities in the 510 area code include: Sunnyvale, Berkeley, Richmond, San Leandro, Alameda, Union City, Walnut Creek, Castro Valley, Hercules, Albany, El Sobrante, and Crockett.
San Jose, officially the City of San José, is the economic, cultural, and political center of Silicon Valley and the largest city in Northern California. With an estimated 2015 population of 1,026,908, it is the third most populous city in California (after Los Angeles and San Diego) and the tenth most populous in United States. Located in the center of the Santa Clara Valley, on the southern shore of San Francisco Bay, San Jose covers an area of 179.97 square miles (466.109/km²). San Jose is the county seat of Santa Clara County, the most affluent county in California. San Jose is the largest city in both the San Francisco Bay Area and the San Jose-San Francisco-Oakland Combined Statistical Area, which contain 7.7 million and 8.7 million people respectively. Before the arrival of the Spanish, the area around San Jose was inhabited by the Ohlone people. San Jose was founded on November 29, 1777, as the Pueblo of San José de Guadalupe, the first civilian town founded in Spanish Alta California. When California gained statehood in 1850, San Jose became the state's first capital. Following World War II, San Jose experienced an economic boom, with a rapid population growth and aggressive annexation of nearby cities and communities carried out in the 1950s and 60s. The rapid growth of the high-technology and electronics industries further accelerated the transition from an agricultural center to an urbanized metropolitan area. Results of the 1990 U.S. Census indicated that San Jose had officially surpassed San Francisco as the most populous city in Northern California. By the 1990s, San Jose and the rest of Silicon Valley had become the global center for the high tech and internet industries.San Jose is considered to be a global city, notable for its affluence and high cost of living. San Jose's location within the booming high tech industry, as a cultural, political, and economic center has earned the city the nickname "Capital of Silicon Valley ". San Jose is one of the wealthiest major cities in the United States and the world, and has the third highest GDP per capita in the world (after Zurich, Switzerland and Oslo, Norway), according to the Brookings Institute. With a median home price of $1,085,000, San Jose has the most expensive housing market in the country and the fifth most expensive housing market in the world, according to the 2017 Demographia International Housing Affordability Survey. Major global tech companies including Cisco Systems, eBay, Adobe Systems, PayPal, Brocade, Samsung, Acer, and Western Digital maintain their headquarters in San Jose, in the center of Silicon Valley.
San Francisco (/ s æ n f r ən ˈ s ɪ s k oʊ /, Spanish for Saint Francis ; Spanish: [san fran.ˈsis.ko]), officially the City and County of San Francisco, is the cultural, commercial, and financial center of Northern California. It is the birthplace of the United Nations. Located at the north end of the San Francisco Peninsula, San Francisco is about 47.9 square miles (124 km 2) in area, making it the smallest county—and the only consolidated city-county —within the state of California. With a density of about 18,451 people per square mile (7,124 people per km 2), San Francisco is the most densely settled large city (population greater than 200,000) in California and the second-most densely populated major city in the United States after New York City. San Francisco is the fourth-most populous city in California, after Los Angeles, San Diego, and San Jose, and the 13th-most populous city in the United States—with a census-estimated 2015 population of 864,816. The city and its surrounding areas are known as the San Francisco Bay Area, and are a part of the larger OMB -designated San Jose-San Francisco-Oakland combined statistical area, the fifth most populous in the nation with an estimated population of 8.7 million.San Francisco was founded on June 29, 1776, when colonists from Spain established Presidio of San Francisco at the Golden Gate and Mission San Francisco de Asís named for St. Francis of Assisi a few miles away. The California Gold Rush of 1849 brought rapid growth, making it the largest city on the West Coast at the time. San Francisco became a consolidated city-county in 1856. After three-quarters of the city was destroyed by the 1906 earthquake and fire, San Francisco (Spanish for Saint Francis) was quickly rebuilt, hosting the Panama-Pacific International Exposition nine years later. In World War II, San Francisco was a major port of embarkation for service members shipping out to the Pacific Theater. After the war, the confluence of returning servicemen, massive immigration, liberalizing attitudes, along with the rise of the " hippie " counterculture, the Sexual Revolution, the Peace Movement growing from opposition to United States involvement in the Vietnam War, and other factors led to the Summer of Love and the gay rights movement, cementing San Francisco as a center of liberal activism in the United States. Politically, the city votes strongly along liberal Democratic Party lines.A popular tourist destination, San Francisco is known for its cool summers, fog, steep rolling hills, eclectic mix of architecture, and landmarks, including the Golden Gate Bridge, cable cars, the former Alcatraz Federal Penitentiary, Fisherman's Wharf, and its Chinatown district. San Francisco is also the headquarters of five major banking institutions and various other companies such as Levi Strauss & Co., Gap Inc., Salesforce.com, Dropbox, Reddit, Square, Inc., Dolby, Airbnb, Weebly, Pacific Gas and Electric Company, Yelp, Pinterest, Twitter, Uber, Lyft, Mozilla, Wikimedia Foundation, and Craigslist. It has several nicknames, including "The City by the Bay", "Fog City", "San Fran", and "Frisco", as well as older ones like "The City that Knows How", "Baghdad by the Bay", "The Paris of the West", or simply "The City". As of 2016 , San Francisco is ranked high on world liveability rankings.
Oakland / ˈ oʊ k l ə n d / is the largest city and the county seat of Alameda County, California, United States. A major West Coast port city, Oakland is the largest city in the East Bay region of the San Francisco Bay Area, the third largest city overall in the San Francisco Bay Area, the eighth largest city in California, and the 45th largest city in the United States, with a population of 419,267 as of 2015 . It serves as a trade center for the San Francisco Bay Area ; its Port of Oakland is the busiest port in the San Francisco Bay, the entirety of Northern California, and the fifth busiest in the United States. The city was incorporated in 1852.Oakland's territory covers what was once a mosaic of California coastal terrace prairie, oak woodland, and north coastal scrub. Its land served as a rich resource when its hillside oak and redwood timber were logged to build San Francisco, and Oakland's fertile flatland soils helped it become a prolific agricultural region. In the late 1860s, Oakland was selected as the western terminal of the Transcontinental Railroad. Following the 1906 San Francisco earthquake, many San Francisco citizens moved to Oakland, enlarging the city's population, increasing its housing stock and improving its infrastructure. It continued to grow in the 20th century with its busy port, shipyards, and a thriving automobile manufacturing industry.Oakland is known for its sustainability practices, including a top-ranking for usage of electricity from renewable resources. Oakland is also known for its history of political activism, as well as its professional sports franchises (such as the Oakland Raiders, Oakland Athletics and the Golden State Warriors) and major corporations, which include health care, dot-com companies, and manufacturers of household products. In addition, due to a steady influx of immigrants during the 20th century, along with thousands of African-American war-industry workers who relocated from the Deep South during the 1940s. Oakland is the most ethnically diverse major city in the country.
The 510 area code lies within the Pacific Daylight Time Zone (or PDT). The current time in Pacific Daylight Time is 11:49 AM on Apr 20, 2021.