|Jefferson County, Colorado|
Jefferson County Courthouse in Golden
|Motto: Gateway to the Rocky Mountains|
Location in the state of Colorado
Colorado's location in the U.S.
|Founded||November 1, 1861|
|Named for||Thomas Jefferson|
774 sq mi (2,005 km²)
764 sq mi (1,979 km²)
9.8 sq mi (25 km²), 1.3%
763/sq mi (295/km²)
|Congressional districts||1st, 2nd, 7th|
|Time zone||Mountain: UTC-7/-6|
Jefferson County, is a county located in the U.S. state of Colorado. As of the 2020 census, the population was 582,910, making it the fourth-most populous county in Colorado. The county seat is Golden, and the most populous city is Lakewood.
Jefferson County is included in the Denver-Aurora-Lakewood, CO Metropolitan Statistical Area. Located along the Front Range of the Rocky Mountains, Jefferson County is adjacent to the state capital of Denver.
In 2010, the center of population of Colorado was located in Jefferson County.
The county's slogan is the "Gateway to the Rocky Mountains", and it is commonly nicknamed Jeffco. The name Jeffco is incorporated in the name of the Jeffco School District, the Jeffco Business Center Metropolitan District No. 1, and several businesses located in Jefferson County. Jeffco is also incorporated in the unofficial monikers of many Jefferson County agencies. The Rocky Mountain Metropolitan Airport operated by Jefferson County was previously known as the Jeffco Airport.
A major employer in Jefferson County is the large Coors Brewing Company in Golden. Also, the state-supported Colorado School of Mines is located in Jefferson County, focusing on topics such as mining, geology, chemistry, and engineering.
On August 25, 1855, the Kansas Territorial Legislature created Arapahoe County to govern the entire western portion of the territory. The county was named for the Arapaho Nation of Native Americans that lived in the region.
On June 22, 1858, gold was discovered along the South Platte River in Arapahoe County (in present-day Englewood). This discovery precipitated the Pike's Peak Gold Rush. Many residents of the mining region felt disconnected from the remote territorial governments of Kansas and Nebraska, so they voted to form their own Territory of Jefferson on October 24, 1859. The following month, the Jefferson Territorial Legislature organized 12 counties for the new territory, including Jefferson County. Jefferson County was named for the namesake of the Jefferson Territory, Thomas Jefferson, the principal author of the Declaration of Independence and the nation's third president. Golden City served as the county seat of Jefferson County. Robert Williamson Steele, Governor of the Provisional Government of the Territory of Jefferson from 1859 to 1861, built his home in the county at Mount Vernon and later at Apex.
The Jefferson Territory never received federal sanction, but during his last week in office, President James Buchanan signed an act which organized the Territory of Colorado on February 28, 1861. That November 1, the new Colorado General Assembly organized the 17 original counties of Colorado, including a new Jefferson County. In 1908, the southern tip of Jefferson County was transferred to Park County, reducing Jefferson County to its present length of 54 miles (87 km). Several annexations by the City & County of Denver and the 2001 consolidation of the City & County of Broomfield removed the east and extreme northwestern portion of the county, respectively.
Jefferson County is one of the few counties in the United States to border as many as ten counties.
- Interstate 70
- I-70 Bus.
- U.S. Highway 6
- U.S. Highway 40
- U.S. Highway 285
- State Highway 8
- State Highway 58
- State Highway 72
- State Highway 74
- State Highway 75
- State Highway 93
- State Highway 121
- State Highway 391
- State Highway 470
- Chatfield Ave
- 44th Ave
- Alderfer/Three Sisters Park
- Apex Park
- Bear Creek Lake Park
- Centennial Cone Park
- Clear Creek Canyon Park
- Coal Creek Canyon
- Crown Hill Park
- Deer Creek Canyon Park
- Elk Meadow Park
- Evergreen Lake
- Fairmount Trail
- Flying J Ranch Park
- Hildebrand Ranch Park
- Hiwan Homestead Museum
- Lair o' the Bear Park
- Lewis Meadows Park
- Lookout Mountain Nature Center
- Matthews/Winters Park
- Meyer Ranch Park
- Mount Falcon Park
- Mount Galbraith Park
- Mount Glennon
- Mount Lindo
- North Table Mountain Park
- Pine Valley Ranch Park
- Ranson/Edwards Homestead Ranch
- Reynolds Park
- Sister City Park
- South Table Mountain Park
- South Valley Park
- Standley Lake Regional Park
- Van Bibber Park
- Welchester Tree Grant Park
- White Ranch Park
- Windy Saddle Park
- Urban Trails
|U.S. Decennial Census|
As of the census of 2000, there were 527,056 people, 206,067 households, and 140,537 families residing in the county. The population density was 683 people per square mile (264 people/km²). There were 212,488 housing units at an average density of 275 people per square mile (106 people/km²). The racial makeup of the county was
90.59% White 0.89% Black or African American 0.75% Native American 2.28% Asian 0.08% Pacific Islander 3.23% from other races2.18% in two or more races
There were 206,067 households, out of which 33.40% had children under age 18 living with them, 55.10% were married couples living together, 9.10% had a female householder with no husband present, and 31.80% were non-families. 24.50% of all households were made up of individuals, of those 6.30% were someone living alone who was 65 years of age or older. The average household size was 2.52, and the average family size was 3.03 persons.
In the county, the population ages were spread out:
25.30% under age 18 8.10% aged 18–24 32.10% from 25–44 24.90% from 45–64 9.60% 65 years of age or olderThe median age was 37 years.
For every 100 females there were 99.00 males. For every 100 females age 18 and over, there were 96.80 males.
The median income for a household in the county was $57,339, and the median income for a family was $67,310. Males had a median income of $45,306 versus $32,372 for females. The per capita income for the county was $28,066. About 3.40% of families and 5.20% of the population were below the poverty line, including 5.80% of those under age 18, and 5.10% of those age 65 or over.
According to a report in the JAMA, residents of Jefferson County had a 2014 life expectancy of 80.02 years.
- Jefferson County School District R-1.
Government and infrastructure
- The Federal Correctional Institution, Englewood is in unincorporated Jefferson County.
- The Rocky Flats Plant produced nuclear weapons in Jefferson County from 1952 until 1989.
- The Jefferson County Public Library, established in 1952.
- The Jefferson County Government Center, also known as the "Taj Mahal".
- The Denver Federal Center, the largest concentration of federal government agencies outside of Washington, D.C., is located in Lakewood.
Jefferson County was once a Republican stronghold, but starting with the 2008 election it has consistently voted Democratic. In 2020 Joe Biden won the largest percentage for a Democratic presidential candidate since 1916.
- Chatfield State Park
- Golden Gate Canyon State Park
- Staunton State Park
National forests and wilderness
- Pike National Forest
- Roosevelt National Forest
- Lost Creek Wilderness
National wildlife refuges
- Rocky Flats National Wildlife Refuge
- Two Ponds National Wildlife Refuge
- South Platte Trail
- American Discovery Trail
- Apex National Recreation Trail
- Big Dry Creek National Recreation Trail
- Colorado Trail
- Platte River Greenway National Recreation Trail
- Two Ponds National Recreation Trail
- Lariat Loop Scenic and Historic Byway
- Applewood Golf Course
- Bear Creek Golf Club
- Evergreen Golf Course
- Foothills Golf Course
- Fossil Trace Golf Course
- Fox Hollow Golf Course
- Heritage Golf Course at Westmoor
- Hiwan Golf Club
- Homestead Golf Course
- Indian Tree Golf Club
- Lake Arbor Golf Course
- Lakewood Country Club
- Racoon Creek Golf Course
- Rolling Hills Country Club
- Bow Mar
- Mountain View
- Superior (part)
- Aspen Park
- Coal Creek (partial)
- Dakota Ridge
- East Pleasant View
- Indian Hills
- Ken Caryl
- West Pleasant View
- Buffalo Creek
- Pine Junction
- Arapahoe County, Kansas Territory
- Colorado metropolitan areas
- Denver-Aurora, CO Combined Statistical Area
- Denver-Aurora-Lakewood, CO Metropolitan Statistical Area
- Front Range Urban Corridor
- Index of Colorado-related articles
- Jefferson County, Colorado Territory
- Jefferson County, Jefferson Territory
- National Register of Historic Places listings in Jefferson County, Colorado
- North Central Colorado Urban Area
- Outline of Colorado
- Pike's Peak Gold Rush
- ^ a b "State & County QuickFacts". United States Census Bureau. https://www.census.gov/quickfacts/fact/table/jeffersoncountycolorado/PST045219.
- ^ "Find a County". National Association of Counties. http://www.naco.org/Counties/Pages/FindACounty.aspx.
- ^ "Centers of Population by State: 2010". United States Census Bureau. https://www.census.gov/geo/reference/docs/cenpop2010/CenPop2010_Mean_ST.txt.
- ^ Gannett, Henry (1905). The Origin of Certain Place Names in the United States. Govt. Print. Off.. pp. 168. https://archive.org/details/bub_gb_9V1IAAAAMAAJ.
- ^ "An Act to provide a temporary Government for the Territory of Colorado". Thirty-sixth United States Congress. 1861-02-28. http://www.colorado.gov/dpa/doit/archives/territory.pdf.
- ^ "US Gazetteer files: 2010, 2000, and 1990". United States Census Bureau. 2011-02-12. https://www.census.gov/geographies/reference-files/time-series/geo/gazetteer-files.html.
- ^ U.S. Decennial Census (Report). United States Census Bureau. https://www.census.gov/programs-surveys/decennial-census.html. Retrieved June 8, 2014.
- ^ Historical Census Browser (Report). University of Virginia. http://mapserver.lib.virginia.edu. Retrieved June 8, 2014.
- ^ Population of Counties by Decennial Census: 1900 to 1990 (Report). United States Census Bureau. https://www.census.gov/population/cencounts/co190090.txt. Retrieved June 8, 2014.
- ^ Ranking Tables for Counties: 1990 and 2000 (Report). Census 2000. United States Census Bureau. PHC-T-4. https://www.census.gov/population/www/cen2000/briefs/phc-t4/tables/tab02.pdf. Retrieved June 8, 2014.
- ^ "U.S. Census" (main website). United States Census Bureau. https://www.census.gov.
- ^ Dwyer-Lindgren, Laura (8 May 2017). "Inequalities in life expectancy among U.S. counties, 1980 to 2014". JAMA Internal Medicine 177 (7): 1003–1011. DOI:10.1001/jamainternmed.2017.0918. PMID 28492829.
- ^ "FCI Englewood Contact Information." Federal Bureau of Prisons. Retrieved on July 28, 2010.
- ^ Leip, David. "Dave Leip's Atlas of U.S. Presidential Elections". http://uselectionatlas.org/RESULTS/.
- Jefferson County Government website
- Colorado County Evolution by Don Stanwyck
- Colorado Historical Society
- Jefferson County Open Space Parks
|Gilpin County||Boulder County||City and County of Broomfield|
|Clear Creek County||Adams County, City and County of Denver, Arapahoe County, and Douglas County|
Jefferson County, Colorado
|Park County||Teller County|