Jefferson County

Jefferson County spans roughly 774 square miles (around 2000 square kilometers) along the Front Range of the Rocky Mountains, bordering the western edge of the Denver metro area. The county includes several towns, with Golden serving as the seat, as well as large tracts of open grassland, pine forests, and steep slopes that rise from plains into middle elevations.

The county was formed in November 1861 and named after the short-lived Jefferson Territory, which miners and settlers had organized before Colorado became official. Golden was chosen as the seat and quickly grew into a supply hub for mines and trade routes heading into the mountains.

The name traces back to the Jefferson Territory, recalling an early attempt at self-governance before statehood came to this part of the Rockies. Residents and visitors today experience a mix of suburban neighborhoods and foothill landscapes, where mountain culture meets the daily rhythms of life near Denver.

Interstate 70 cuts through the county from east to west, offering quick access to the different towns and recreational areas along the way. Many roads climb rapidly as you move from the suburbs toward the mountains, and driving conditions can vary depending on season and weather.

The county protects large parklands such as Bear Creek Lake Park and Elk Meadow Park, which offer many trails and picnic spots surrounded by mountain forests and lakes. These areas draw locals looking for quiet time in nature without traveling far from home.

Location: Colorado

Inception: 1861

Capital city: Golden

Shares border with: Boulder County, Broomfield County, Adams County, Denver County, Arapahoe County, Douglas County, Teller County, Park County, Clear Creek County, Gilpin County

Website: http://jeffco.us

GPS coordinates: 39.59000,-105.25000

Latest update: December 4, 2025 23:41