Jefferson County | |
|---|---|
 Jefferson County Courthouse in Golden, nicknamed "Colorado's Taj Mahal" for its dome architecture | |
 Flag  Seal | |
| Motto: Gateway to the Rocky Mountains | |
 Location within the U.S. state of Colorado | |
 Colorado's location within the U.S. | |
| Coordinates: 39°35′N 105°15′W / 39.59°N 105.25°W | |
| Country |  United States |
| State |  Colorado |
| Founded | November 1, 1861 |
| Named for | Jefferson Territory |
| Seat | Golden |
| Largest city | Lakewood |
| Area | |
• Total | 774 sq mi (2,000 km2) |
| • Land | 764 sq mi (1,980 km2) |
| • Water | 9.8 sq mi (25 km2) 1.3% |
| Population (2020) | |
• Total | 582,910 |
• Estimate (2023) | 576,366  |
| • Density | 750/sq mi (290/km2) |
| Time zone | UTC−7 (Mountain) |
| • Summer (DST) | UTC−6 (MDT) |
| Congressional districts | 1st, 2nd, 6th, 7th |
| Website | www |
Jefferson County is a county located in the U.S. state of Colorado. As of the 2020 census, the population was 582,910,[1] making it the fourth-most populous county in Colorado. The county seat is Golden,[2] 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.[3]
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, a university specializing in mining, geology, chemistry, and engineering is located in Jefferson County.
- ^ "State & County QuickFacts". United States Census Bureau. Retrieved September 5, 2021.
- ^ "Find a County". National Association of Counties. Archived from the original on May 31, 2011. Retrieved June 7, 2011.
- ^ "Centers of Population by State: 2010". United States Census Bureau. Archived from the original on January 3, 2014. Retrieved June 8, 2014.