Map of Boulder County, Colorado

Boulder County is a county located in the U.S. state of Colorado of the United States. As of the 2020 census, the population was 330,758. The most populous municipality in the county and the county seat is Boulder.

Boulder County comprises the Boulder, Colorado Metropolitan Statistical Area, which is included in the Denver–Aurora, Colorado Combined Statistical Area.

Boulder County overview:
Name:	Boulder County
FIPS code:	08-013
State:	Colorado
Founded:	November 1, 1861
Named for:	large granite boulders in area
Seat:	Boulder
Largest city:	Boulder
Total Area:	740 sq mi (1,900 km²)
Land Area:	726 sq mi (1,880 km²)
Total Population:	329,543
Population Density:	460/sq mi (176/km²)
Time zone:	UTC−7 (Mountain)
Summer Time Zone (DST):	UTC−6 (MDT)
Website:	www.bouldercounty.org

Boulder County location map. Where is Boulder County?

Boulder County location on the U.S. Map. Where is Boulder County. — Location of Boulder County in the the United States.

Boulder County location on the Colorado map. Where is Boulder County. — Location of Boulder County in Colorado.

History

Boulder County was one of the original 17 counties created by the Territory of Colorado on November 1, 1861. The county was named for Boulder City and Boulder Creek, so named because of the abundance of boulders in the creek which hampered early gold prospecting efforts. Boulder County retains essentially the same borders as in 1861, although a 27.5 square miles (71.2 km) of its southeastern corner and its approximate population of 40,000 became part of the City and County of Broomfield in 2001.

Before the arrival of the first US settlers, the area was occupied by Native Americans led by Chief Niwot on the plains and seasonally by Utes in the mountains to the west. The first European American settlers were gold prospectors led by Captain Thomas Aikins. His group of about twenty settled at the mouth of Boulder Creek Canyon on October 17, 1858. Chief Niwot told them not to stay and it is said they promised to move into the mountains to prospect in the spring. However in February 1859, they founded the town of Boulder. At about the same time, they also founded the first Gold Mining town in what would become Colorado, Gold Hill which is about 10 miles west from Boulder. Gold Hill was founded because of the placer gold discovered there. The area was the site of the first commercial scale placer mine in Colorado, producing over 5,500 ounces of gold in the first year of operations (1859).

Boulder County Road Map

Boulder CountyStreet Map. — Street map of Boulder County, Colorado. Source: OpenStreetMap (OSM)

Boulder CountyMap — Boulder Countypolitical map.

Geography

According to the U.S. Census Bureau, the county has a total area of 740 square miles (1,900 km), of which 726 square miles (1,880 km) is land and 14 square miles (36 km) (1.9%) is water.

Adjacent counties

Larimer County, Colorado – north
Weld County, Colorado – east
City and County of Broomfield, Colorado – southeast
Jefferson County, Colorado – south
Gilpin County, Colorado – south
Grand County, Colorado – west

Major Highways

U.S. Highway 36 (Denver-Boulder Turnpike)
U.S. Highway 287
State Highway 7
State Highway 42
State Highway 52
State Highway 66
State Highway 72
State Highway 93
State Highway 119
State Highway 170
Northwest Parkway (tollway)

National protected areas

Arapaho National Forest
Roosevelt National Forest
Indian Peaks Wilderness
James Peak Wilderness

Rocky Mountain National Park is in Boulder County, Larimer County, and Grand County. Longs Peak, the park’s highest summit at 4,345 meters (14,255 feet) elevation, is located in Boulder County.

State protected area

Eldorado Canyon State Park

Scenic trails and byways

Continental Divide National Scenic Trail
Peak to Peak Scenic and Historic Byway

Historic district

Colorado Chautauqua National Historic District