San Mateo County, California facts for kids
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San Mateo County, California
|County of San Mateo|
All of California in One County
Location in the state of California
California's location in the United States
|Region||San Francisco Bay Area|
|Incorporated||19 April 1856|
|Named for||Saint Matthew (English translation)|
|County seat||Redwood City|
|Largest city||Daly City (population)
Redwood City (area)
|• Total||744 sq mi (1,930 km2)|
|• Land||448 sq mi (1,160 km2)|
|• Water||293 sq mi (760 km2)|
|Highest elevation||2,603 ft (793 m)|
| • Estimate
|• Density||1,693/sq mi (654/km2)|
|Time zone||UTC-8 (Pacific Time Zone)|
|• Summer (DST)||UTC-7 (Pacific Daylight Time)|
|Area codes||415/628, 650|
|GNIS feature ID||277305|
San Mateo County is included in the San Francisco-Oakland-Hayward, CA Metropolitan Statistical Area, and is part of the San Francisco Bay Area, the nine counties bordering San Francisco Bay. It covers most of the San Francisco Peninsula. San Francisco International Airport is located at the northern end of the county, and Silicon Valley begins at the southern end. The county's built-up areas are mostly suburban with some areas being very urban, and are home to several corporate campuses.
- Notable structures
- Images for kids
San Mateo County was formed in 1856 after San Francisco County, one of the state's 18 original counties since California's statehood in 1850, was split apart. Until 1856, San Francisco's city limits extended west to Divisadero Street and Castro Street, and south to 20th Street. In response to the lawlessness and vigilantism that escalated rapidly between 1855 and 1856, the California government decided to divide the county. A straight line was then drawn across the tip of the San Francisco Peninsula just north of San Bruno Mountain. Everything south of the line became the new San Mateo County while everything north of the line became the new consolidated City and County of San Francisco, to date the only consolidated city-county in California. The consolidated city-county of San Francisco was formed by a bill introduced by Horace Hawes, signed by the governor on 19 April 1856. San Mateo County was officially organized on 18 April 1857 under a bill introduced by Senator T.G. Phelps. The 1857 bill defined the southern boundary of San Mateo County as following the south branch of San Francisquito Creek to its source in the Santa Cruz Mountains and thence due west to the Pacific Ocean, and named Redwood City as the county seat. San Mateo County then annexed part of northern Santa Cruz County in March 1868, including Pescadero and Pigeon Point.
Although the forming bill named Redwood City the county seat, a May 1856 election marked by "unblushing frauds ... perpetuated on an unorganized and wholly unprotected community by thugs and ballot stuffers from San Francisco" named Belmont the county seat. The election results were declared illegal and the county government was moved to Redwood City, with land being donated from the original Pulgas Grant for the county government on 27 February 1858. Redwood City's status as county seat was upheld in two succeeding elections in May 1861 and 9 December 1873, defeating San Mateo and Belmont. Another election in May 1874 named San Mateo the county seat, but the state supreme court overturned that election on 24 February 1875 and the county seat has been in Redwood City since.
San Mateo County bears the Spanish name for Saint Matthew. As a place name, San Mateo appears as early as 1776 and several local geographic features were also designated San Mateo on early maps including variously: a settlement, an arroyo, a headland jutting into the Pacific (Point Montara), and a large land holding (Rancho San Mateo). Until about 1850, the name appeared as San Matheo.
According to the U.S. Census Bureau, the county has a total area of 741 square miles (1,920 km2), of which 448 square miles (1,160 km2) is land and 293 square miles (760 km2) (40%) is water. It is the third-smallest county in California by land area. A number of bayside watercourses drain the eastern part of the county including San Bruno Creek and Colma Creek. Streams draining the western county include Frenchmans Creek, Pilarcitos Creek, Naples Creek, Arroyo de en Medio, and Denniston Creek. These streams originate along the northern spur of the Santa Cruz Mountains that run through the county. The northern and north-east parts of the county are very heavy densely populated with largely urban and suburban areas, with many of its cities as edge-cities for the Bay Area, whilst the deep south and the west central parts of the county are less heavy densely populated with more rural environment and coastal beaches areas.
San Mateo County straddles the San Francisco Peninsula, with the Santa Cruz Mountains running its entire length. The county encompasses a variety of habitats including estuarine, marine, oak woodland, redwood forest, coastal scrub and oak savannah. There are numerous species of wildlife present, especially along the San Francisco Bay estuarine shoreline, San Bruno Mountain, Fitzgerald Marine Reserve and the forests on the Montara Mountain block. Several creeks discharge to the San Francisco Bay including San Mateo Creek and Laurel Creek and several coastal streams discharge to the Pacific Ocean such as Frenchmans Creek and San Vicente Creek.
Año Nuevo State Marine Conservation Area and Greyhound Rock State Marine Conservation Area are two adjoining marine protected areas off the coast of San Mateo County. Like underwater parks, these marine protected areas help conserve ocean wildlife and marine ecosystems.
Flora and fauna
The county is home to several endangered species including the San Francisco garter snake and the San Bruno elfin butterfly, both of which are endemic to San Mateo County. The endangered California clapper rail is also found on the shores of San Francisco Bay, in the cities of Belmont and San Mateo. The endangered wildflower Hickman's potentilla is found near the Pacific Ocean on the lower slopes of Montara Mountain. The endangered wildflowers White-rayed pentachaeta, Pentachaeta bellidiflora, San Mateo Woolly Sunflower, Eriophyllum latilobum, Marin Dwarf Flax, Hesperolinon congestum and the San Mateo Thornmint, Acanthomintha duttonii, are found in the vicinity of the Crystal Springs Reservoir.
In May 2014, a California condor was spotted near Pescadero, a coastal community south of San Francisco—it was the first California condor spotted in San Mateo County since 1904. The Condor, tagged with the number "597," and also known as "Lupine", is one of 439 condors living in the wild or captivity in California, Baja California and Arizona. The three-year-old female flew more than 100 miles (160 km) north from Pinnacles National Park, in San Benito County, on May 30, and landed on a private, forested property near Pescadero, on the San Mateo County Coast, where it was photographed by a motion-activated wildlife camera. Harold Heath, Professor Emeritus, of Stanford University was responsible for the 1904 sighting, 1 mile (1.6 km) west of the University campus.
National protected areas
- Don Edwards San Francisco Bay National Wildlife Refuge (part)
- Golden Gate National Recreation Area (part)
Marine protected area
See this county page for trail descriptions.
- Alpine Trail
- Bog Trail
- Cañada Trail
- Crystal Springs Trail
- Edgewood Trail
- Ralston Trail
- San Andreas Trail
- Sand Hill Trail
- Sawyer Camp Trail
- Skyline Trail
- Sheep Camp Trail
- Sweeney Ridge Trail
- Hiking trails in San Mateo County
- Coyote Point Recreation Area
- Coyote Point Marina
- Crystal Springs
- Edgewood Park and Natural Reserve
- Fitzgerald Marine Reserve
- Flood Park (County)
- Heritage Grove
- Huddart Park
- Junipero Serra County Park
- Pescadero Creek Park
- Russian Ridge Open Space Preserve
- Sam MacDonald Park
- San Bruno Mountain (County Park)
- San Mateo Fishing Pier
- San Mateo County Memorial Park
- San Pedro Valley County Park
- Sanchez Adobe
- Woodside Store
- Wunderlich Park (New)
San Mateo County had one of the largest Tongan communities outside of Tonga, with an estimated 13,000 Tongan Americans.
|Population, race, and income|
|Black or African American||20,507||2.9%|
|American Indian or Alaska Native||2,469||0.3%|
|Native Hawaiian or other Pacific Islander||10,556||1.5%|
|Some other race||47,756||6.7%|
|Two or more races||31,017||4.4%|
|Hispanic or Latino (of any race)||177,003||24.9%|
|Per capita income||$45,346|
|Median household income||$87,633|
|Median family income||$104,370|
Places by population, race, and income
|Places by population and race|
||Asian||Black or African
||Hispanic or Latino
(of any race)
|East Palo Alto||City||28,077||54.3%||15.5%||3.0%||17.5%||9.8%||62.1%|
|Emerald Lake Hills||CDP||4,273||86.3%||1.8%||10.9%||1.0%||0.0%||4.6%|
|Half Moon Bay||City||11,228||84.7%||10.4%||3.7%||1.1%||0.0%||29.8%|
|North Fair Oaks||CDP||14,666||70.1%||22.6%||4.0%||1.7%||1.6%||74.3%|
|South San Francisco||City||62,822||41.5%||16.8%||35.9%||2.4%||3.5%||33.7%|
|West Menlo Park||CDP||3,600||84.0%||3.7%||10.2%||2.2%||0.0%||5.6%|
|Places by population and income|
|Place||Type||Population||Per capita income||Median household income||Median family income|
|East Palo Alto||City||28,077||$18,014||$50,137||$49,974|
|Emerald Lake Hills||CDP||4,273||$82,988||$172,619||$176,250|
|Half Moon Bay||City||11,228||$47,909||$96,208||$120,357|
|North Fair Oaks||CDP||14,666||$22,273||$53,868||$50,480|
|South San Francisco||City||62,822||$31,563||$75,543||$84,027|
|West Menlo Park||CDP||3,600||$78,879||$132,009||$183,355|
|U.S. Decennial Census
The 2010 United States Census reported that San Mateo County had a population of 718,451. The racial makeup of San Mateo County was 383,535 (53.4%) White, 20,436 (2.8%) African American, 3,306 (0.5%) Native American, 178,118 (24.8%) Asian (9.8% Filipino, 9.0% Chinese, 1.9% Indian, 1.2% Japanese, 0.8% Korean, 0.5% Vietnamese, 0.3% Burmese, 0.1% Pakistani), 10,317 (1.4%) Pacific Islander (0.6% Tongan, 0.3% Samoan, 0.2% Fijian, 0.1% Native Hawaiian), 84,529 (11.8%) from other races, and 38,210 (5.3%) from two or more races. Hispanic or Latino of any race were 182,502 persons (25.4%); 15.7% of San Mateo County is Mexican, 2.7% Salvadoran, 1.2% Guatemalan, 1.2% Nicaraguan, 0.7% Peruvian, 0.6% Puerto Rican, 0.2% Colombian, and 0.2% Cuban.
|Population reported at 2010 United States Census|
(of any race)
|San Mateo County||718,451||383,535||20,436||3,306||178,118||10,317||84,529||38,210||182,502|
cities and towns
(of any race)
|East Palo Alto||28,155||8,104||4,704||120||1,057||2,118||10,694||1,358||18,147|
|Half Moon Bay||11,324||8,580||82||71||490||9||1,710||382||3,563|
|South San Francisco||63,632||23,760||1,625||395||23,293||1,111||9,598||3,850||21,645|
(of any race)
|Emerald Lake Hills||4,278||3,655||39||5||322||15||56||186||288|
|North Fair Oaks||14,687||7,060||235||143||548||219||5,728||754||10,731|
|West Menlo Park||3,659||2,983||28||2||416||4||52||174||201|
(of any race)
|All others not CDPs (combined)||15,806||11,667||156||74||1,608||85||1,583||633||3,542|
As of the census of 2009, there were 714,936 people, 258,648 households, and 174,582 families residing in the county. The population density was 2,753/sq mi (825/km²). There were 284,471 housing units at an average density of 789/sq mi (432/km²). 7.4% were of Italian, 7.1% Irish, 7.0% German and 5.3% English ancestry according to Census 2000. 46.9% spoke English, 28.4% Spanish, 6.2% Tagalog, 4.0% Chinese or Mandarin and 1.1% Cantonese, and other language 4.2%, as their first language from estimate census 2009.
There were 258,648 households out of which 30% had children under the age of 18, 48.6% were married couples living together, 14.7% had a female householder with no husband present, and 41.7% were non-families. 31.5% of all households were made up of individuals and 6.2% had someone living alone who was 65 years of age or older. The average household size was 3.79 and the average family size was 4.44.
In the county, the population was spread out with 28.6% under the age of 18, 15.9% from 18 to 24, 25.8% from 25 to 44, 21% from 45 to 64, and 9.7% who were 65 years of age or older. The median age was 31 years. For every 100 females there were 97.8 males. For every 100 females age 18 and over, there were 95.1 males.
The median income for a household in the county was $69,306, and the median income for a family was $77,737. Males had a median income of $48,342 versus $45,383 for females. The per capita income for the county was $36,045. About 6.42% of families and 9.51% of the population were below the poverty line, including 10.01% of those under age 18 and 8.52% of those age 65 or over.
SamTrans (San Mateo County Transit District) provides local bus service within San Mateo County. Local and commuter bus routes also operate into San Francisco.
Caltrain, the commuter rail system, traverses the county from north to south, running alongside the Highway 101 corridor for most of the way.
Caltrain, BART, and SamTrans converge at the Millbrae Intermodal station.
San Mateo County does own two general aviation airports: Half Moon Bay Airport and San Carlos Airport.
The only deepwater port in South San Francisco Bay is the Port of Redwood City, situated along Redwood Creek, originally created as a lumber embarcadero in 1850. The San Mateo Harbor Harbor District manages the Pillar Point Harbor and Oyster Point Marina. Ferry connections connect Oyster Point to Jack London Square in Oakland and the Alameda Ferry Terminal in Alameda.
There are a number of well known structures within San Mateo County:
- Carolands Mansion, Hillsborough
- Cow Palace, Daly City
- Crocker Mansion, Hillsborough
- Crystal Springs Reservoir, unincorporated central part of county
- CuriOdyssey, San Mateo
- Filoli Mansion, Woodside
- Notre Dame de Namur University, Belmont, which incorporates Ralston Hall
- Pigeon Point Lighthouse, Pescadero
- Point Montara Lighthouse, Montara
- Pulgas Water Temple, Woodside
- Sanchez Adobe, Pacifica
- San Mateo County History Museum, Redwood City
- San Francisco International Airport
- Stanford Linear Accelerator Center, Menlo Park
The population ranking of the following table is based on the 2010 census of San Mateo County.
† county seat
|Rank||City/Town/etc.||Municipal type||Population (2010 Census)|
|3||† Redwood City||City||76,815|
|4||South San Francisco||City||63,632|
|11||East Palo Alto||City||28,155|
|14||North Fair Oaks||CDP||14,687|
|15||Half Moon Bay||City||11,324|
|22||Emerald Lake Hills||CDP||4,278|
|25||West Menlo Park||CDP||3,659|
Images for kids
San Mateo County Government Center in Redwood City, facing northwest
San Mateo County, California Facts for Kids. Kiddle Encyclopedia.