Jefferson County
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AI overview
Jefferson County is a county in Colorado that includes suburban areas west of Denver. It matters because it's one of Colorado's most populous counties and includes significant communities and economic activity in the Denver metropolitan region.
AI-generated from the Wikipedia summary — may contain errors.
Key facts
- Country
- United States
- State
- Colorado
- Founded
- November 1, 1861
- Named after
- Jefferson Territory
- Seat
- Golden
- Largest city
- Lakewood
- Total
- 774 sq mi (2,000 km )
- Land
- 764 sq mi (1,980 km )
- Water
- 9.8 sq mi (25 km ) 1.3%
- Estimate 2025
- 580,451
- Density
- 763/sq mi (295/km )
- Time zone
- UTC−7 ( Mountain )
- Summer dst
- UTC−6 ( MDT )
Article
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, which was Colorado's capital twice, and its 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.