A map of the United States of America with the State of Colorado highlighted.
A map of the United States of America with the State of Colorado highlighted.

The U.S. state of Colorado is divided into 64 counties. Counties are important units of government in Colorado since there are no townships or other minor civil divisions. Two of these counties, Broomfield and Denver, have consolidated city and county governments.

Colorado's ISO 3166-2:US state code is US-CO and its ANSI INCITS 38:2009 state code is 08.

History

On November 1, 1861, the new Territory of Colorado created 17 original counties: Arapahoe, Boulder, Clear Creek, Costilla, Douglas, El Paso, Fremont, Gilpin, Guadalupe, Huerfano, Jefferson, Lake, Larimer, Park, Pueblo, Summit, and Weld; plus the Cheyenne Reserve.[1][2]

On February 9, 1866, the first new county, Las Animas, was created, followed by Saguache in December of that year. Bent County was created in February 1870, followed by Greenwood the following month. On February 2, 1874, Grand County and Elbert County were formed, and on February 10, La Plata, Hinsdale, and Rio Grande counties were created. Greenwood was absorbed into Bent on February 5. The last county to be created under the Colorado Territory name was San Juan County, created three months before statehood.

By the time Colorado became a state on August 1, 1876, it had only 26 counties. In January 1877, Routt and Ouray were formed, followed by Gunnison and Custer counties in March. In February 1879, Chaffee County was created. From February 8–10, 1879, Lake county was renamed Carbonate County. In 1881, Dolores County and Pitkin County were created. In 1883, Montrose, Mesa, Garfield, Eagle, Delta, and San Miguel counties were formed, leaving the total number of counties at 39. The number rose to 40 in 1885 with the creation of Archuleta County on April 14. Washington County and Logan County were both created in 1887. Between February 19 and April 16 in 1889, Morgan, Yuma, Cheyenne, Otero, Rio Blanco, Phillips, Sedgwick, Kiowa, Kit Carson, Lincoln, Prowers, Baca, and Montezuma counties were formed, bringing the total to 55. By 1900, Mineral County and Teller County had been added. On November 15, 1902, Arapahoe County was split into Adams and South Arapahoe Counties, and Denver was consolidated as a city and county from portions of both newly formed counties on December 1, 1902.[3] By 1912, Jackson County, Moffat County, and Crowley County had been created. Alamosa was created in 1913, and in 2001, Broomfield was consolidated as a city and county, bringing the total to 64 counties.

Table of counties

County
FIPS code[4][a] County seat[5][6] Est.[7] Formed from[7] Etymology[7] Population[8] Area[5] Map
Adams County 001 Brighton 1902-11-15 Split from Arapahoe County. Named in honor of Alva Adams, the 5th, 10th, and 14th Governor of the State of Colorado. 522,140 1,182.29 sq mi
(3,062 km2)
State map highlighting Adams County


Alamosa County 003 Alamosa 1913-03-08 Split from Costilla County and Conejos County. Named for the cottonwood trees which grow along the Rio Grande and its tributaries. Alamosa is a Spanish word for a cottonwood grove. 16,547 723.21 sq mi
(1,873 km2)
State map highlighting Alamosa County


Arapahoe County 005 Littleton 1861-11-01 Created as one of the 17 original counties of the Territory of Colorado. Renamed South Arapahoe County for the five months from November 15, 1902 to April 11, 1903. Named for predecessor Arapahoe County, Kansas Territory, which in turn was named for the Arapaho Nation of Native Americans. 654,900 804.41 sq mi
(2,083 km2)
State map highlighting Arapahoe County


Archuleta County 007 Pagosa Springs 1885-04-14 Split from Conejos County. Named in honor of Colorado State Senator Antonio D. Archuleta and his father, José Manuel Archuleta. 13,790 1,354.53 sq mi
(3,508 km2)
State map highlighting Archuleta County


Baca County 009 Springfield 1889-04-16 Split from Las Animas County. Named in honor of pioneer and Colorado territorial legislator Felipe Baca. 3,514 2,558.48 sq mi
(6,626 km2)
State map highlighting Baca County


Bent County 011 Las Animas 1870-02-11 Split from Huerfano County and former Cheyenne and Arapaho tribal land. Named in honor of frontier trader William Bent. 5,759 1,541.07 sq mi
(3,991 km2)
State map highlighting Bent County


Boulder County 013 Boulder 1861-11-01 Created as one of the 17 original counties of the Territory of Colorado. Named for the abundance of granite boulders along Boulder Creek. 329,543 740.48 sq mi
(1,918 km2)
State map highlighting Boulder County


City and County of Broomfield 014 Broomfield 2001-11-15 Split from Boulder, Adams, Jefferson, and Weld counties and reorganized as a consolidated city and county. Named for the broom corn that was formerly grown in the area. 75,325 33.57 sq mi
(87 km2)
State map highlighting City and County of Broomfield


Chaffee County 015 Salida 1879-02-10 Split from Carbonate County. Named in honor of Jerome Bunty Chaffee, one of Colorado's first two U.S. Senators from 1876 to 1879. 20,074 1,014.12 sq mi
(2,627 km2)
State map highlighting Chaffee County


Cheyenne County 017 Cheyenne Wells 1889-03-25 Split from Elbert and Bent counties. Named for the Cheyenne Nation of Native Americans. 1,707 1,781.90 sq mi
(4,615 km2)
State map highlighting Cheyenne County


Clear Creek County 019 Georgetown 1861-11-01 Created as one of the 17 original counties of the Territory of Colorado. Named for Clear Creek which originates in the county. 9,446 396.53 sq mi
(1,027 km2)
State map highlighting Clear Creek County


Conejos County 021 Conejos 1861-11-01 Guadalupe County, one of the 17 original counties of the Territory of Colorado, was renamed Conejos County after six days on November 7, 1861. Named for the cottontail rabbits in the area. Conejos is a Spanish word for rabbits. 7,612 1,290.22 sq mi
(3,342 km2)
State map highlighting Conejos County


Costilla County 023 San Luis 1861-11-01 Created as one of the 17 original counties of the Territory of Colorado. Named for the Costilla River. Costilla is a Spanish word meaning either little rib or furring timber. 3,625 1,229.38 sq mi
(3,184 km2)
State map highlighting Costilla County


Crowley County 025 Ordway 1911-05-29 Split from Otero County. Named in honor of Colorado State Senator John H. Crowley. 6,012 800.27 sq mi
(2,073 km2)
State map highlighting Crowley County


Custer County 027 Westcliffe 1877-03-09 Split from Fremont County. Named in memory of George Armstrong Custer, (1839 - 1876), the U.S. Army colonel defeated and killed at the Battle of the Little Bighorn. 5,045 739.24 sq mi
(1,915 km2)
State map highlighting Custer County


Delta County 029 Delta 1883-02-11 Split from Gunnison County. Named for the town of Delta located at the delta of the Uncompahgre River. 31,661 1,149.44 sq mi
(2,977 km2)
State map highlighting Delta County


City and County of Denver 031 Denver 1902-12-01 The original Arapahoe County Seat was split from Arapahoe and the newly-created Adams Counties, and reorganized as a consolidated city and county. Named to curry favor with James W. Denver, Governor of the Territory of Kansas from 1857 to 1859. 711,463 155.66 sq mi
(403 km2)
State map highlighting City and County of Denver


Dolores County 033 Dove Creek 1881-03-04 Split from Ouray County. Named for the Dolores River, which was originally named el Rio de Nuestra Senora de los Dolores, which is Spanish for the River of our Lady of Sorrows. 2,397 1,076.93 sq mi
(2,789 km2)
State map highlighting Dolores County


Douglas County 035 Castle Rock 1861-11-01 Created as one of the 17 original counties of the Territory of Colorado. Named in honor of Stephen Arnold Douglas, (1813 - 1861), U.S. Senator from Illinois from 1847 to 1861. 368,990 842.30 sq mi
(2,182 km2)
State map highlighting Douglas County


Eagle County 037 Eagle 1883-02-11 Split from Summit County. Named for the Eagle River which originates in the county. 55,727 1,700.76 sq mi
(4,405 km2)
State map highlighting Eagle County


El Paso County 041 Colorado Springs 1861-11-01 Created as one of the 17 original counties of the Territory of Colorado. Named for Ute Pass, which connects the Great Plains to South Park and was formerly located within the county. El Paso means the pass in Spanish. 737,867 2,128.60 sq mi
(5,513 km2)
State map highlighting El Paso County


Elbert County 039 Kiowa 1874-02-02 Split from Douglas County. Named in honor of Samuel Hitt Elbert, the sixth Governor of the Territory of Colorado. 27,128 1,849.08 sq mi
(4,789 km2)
State map highlighting Elbert County


Fremont County 043 Cañon City 1861-11-01 Created as one of the 17 original counties of the Territory of Colorado. Named in honor of John Charles Frémont (1813 - 1890), the explorer, U.S. Army general, and U.S. Senator from California. 49,661 1,533.09 sq mi
(3,971 km2)
State map highlighting Fremont County


Garfield County 045 Glenwood Springs 1883-02-10 Split from Summit County. Named in honor of James Abram Garfield (1831 - 1881), the twentieth President of the United States. 62,161 2,958.23 sq mi
(7,662 km2)
State map highlighting Garfield County


Gilpin County 047 Central City 1861-11-01 Created as one of the 17 original counties of the Territory of Colorado. Named in honor of William Gilpin, the first Governor of the Territory of Colorado. 5,873 150.15 sq mi
(389 km2)
State map highlighting Gilpin County


Grand County 049 Hot Sulphur Springs 1874-02-02 Split from Summit County. Named for the Grand River which originates in the county. The Grand River was renamed the Colorado River in 1921, but the county retains the original name. 15,860 1,868.53 sq mi
(4,839 km2)
State map highlighting Grand County


Gunnison County 051 Gunnison 1877-03-09 Split from Lake County. Named in honor of John Williams Gunnison, the U.S. Army captain who explored the region. 17,281 3,259.22 sq mi
(8,441 km2)
State map highlighting Gunnison County


Hinsdale County 053 Lake City 1874-02-10 Split from Lake, Conejos, and Costilla counties. Named in honor of George Aaron Hinsdale, a Lieutenant Governor of the Territory of Colorado. 781 1,123.35 sq mi
(2,909 km2)
State map highlighting Hinsdale County


Huerfano County 055 Walsenburg 1861-11-01 Created as one of the 17 original counties of the Territory of Colorado. Named for Huerfano Butte, a solitary volcanic plug. Huérfano is a Spanish word meaning orphan. 6,920 1,592.37 sq mi
(4,124 km2)
State map highlighting Huerfano County


Jackson County 057 Walden 1909-05-05 Split from Larimer County. Named in honor of Andrew Jackson (1767 - 1845), the seventh President of the United States. 1,363 1,619.75 sq mi
(4,195 km2)
State map highlighting Jackson County


Jefferson County 059 Golden 1861-11-01 Created as one of the 17 original counties of the Territory of Colorado. Named for its extralegal predecessor county, Jefferson County, Jefferson Territory, which in turn was named in honor of Thomas Jefferson (1743 - 1826), the author of the Declaration of Independence and the third President of the United States. 579,581 772.85 sq mi
(2,002 km2)
State map highlighting Jefferson County


Kiowa County 061 Eads 1889-04-11 Split from Bent County. Named for the Kiowa Nation of Native Americans. 1,452 1,785.90 sq mi
(4,625 km2)
State map highlighting Kiowa County


Kit Carson County 063 Burlington 1889-04-11 Split from Elbert County. Named in honor of Christopher Houston "Kit" Carson, the famous frontier scout and soldier. 6,950 2,162.43 sq mi
(5,601 km2)
State map highlighting Kit Carson County


La Plata County 067 Durango 1874-02-10 Split from Lake and Conejos counties. Named for the many silver deposits in the area. La plata is a Spanish expression for the silver. 56,250 1,700.44 sq mi
(4,404 km2)
State map highlighting La Plata County


Lake County 065 Leadville 1861-11-01 Created as one of the 17 original counties of the Territory of Colorado. Renamed Carbonate County for the two days from February 8–10, 1879. Named for the Twin Lakes in the county. 7,407 383.55 sq mi
(993 km2)
State map highlighting Lake County


Larimer County 069 Fort Collins 1861-11-01 Created as one of the 17 original counties of the Territory of Colorado. Named in honor of William Larimer, a pioneer entrepreneur. 362,533 2,631.75 sq mi
(6,816 km2)
State map highlighting Larimer County


Las Animas County 071 Trinidad 1866-02-09 Split from Huerfano County. Named for the Purgatoire River, which was originally named el Rio de las Animas Perdidas, which is Spanish for the River of the Souls in Purgatory. 14,633 4,773.27 sq mi
(12,363 km2)
State map highlighting Las Animas County


Lincoln County 073 Hugo 1889-04-11 Split from Elbert and Bent counties. Named in honor of Abraham Lincoln (1809 - 1865), the sixteenth President of the United States. 5,688 2,585.21 sq mi
(6,696 km2)
State map highlighting Lincoln County


Logan County 075 Sterling 1887-02-25 Split from Weld County. Named in honor of John Alexander Logan (1826 - 1886), a U.S. Army general and U.S. Senator from Illinois. 21,487 1,845.31 sq mi
(4,779 km2)
State map highlighting Logan County


Mesa County 077 Grand Junction 1883-02-14 Split from Gunnison County. Named for the mesa formations which are widespread through the area. 157,335 3,345.69 sq mi
(8,665 km2)
State map highlighting Mesa County


Mineral County 079 Creede 1893-03-27 Split from Hinsdale, Rio Grande, and Saguache counties. Named from the plentiful mineral deposits found in the area. 924 878.16 sq mi
(2,274 km2)
State map highlighting Mineral County


Moffat County 081 Craig 1911-02-27 Split from Routt County. Named in honor of railroad pioneer David H. Moffat. 13,185 4,755.86 sq mi
(12,318 km2)
State map highlighting Moffat County


Montezuma County 083 Cortez 1889-04-16 Split from La Plata County. Named in honor of Aztec leader Moctezuma II. Ruins in the area were once thought to be Aztec. 26,175 2,035.80 sq mi
(5,273 km2)
State map highlighting Montezuma County


Montrose County 085 Montrose 1883-02-11 Split from Gunnison County. Named for the town of Montrose, which in turn was probably named from the novel A Legend of Montrose, published in 1819 by Walter Scott. 43,168 2,246.43 sq mi
(5,818 km2)
State map highlighting Montrose County


Morgan County 087 Fort Morgan 1889-02-19 Split from Weld County. Named for old Fort Morgan, which in turn was named in honor of U.S. Army Colonel Christopher A. Morgan. 29,008 1,293.83 sq mi
(3,351 km2)
State map highlighting Morgan County


Otero County 089 La Junta 1889-03-25 Split from Bent County. Named in honor of Miguel A. Otero of the prominent Otero family of the Southwest. 18,594 1,267.66 sq mi
(3,283 km2)
State map highlighting Otero County


Ouray County 091 Ouray 1877-01-18 Split from Hinsdale and Lake counties. Renamed Uncompaghre County for four days from 1883-02-27, to 1883-03-02. Named in honor of Ouray, a Ute Native American leader. 5,035 542.30 sq mi
(1,405 km2)
State map highlighting Ouray County


Park County 093 Fairplay 1861-11-01 Created as one of the 17 original counties of the Territory of Colorado. Named for South Park which occupies most of the county. 17,720 2,209.36 sq mi
(5,722 km2)
State map highlighting Park County


Phillips County 095 Holyoke 1889-03-27 Split from Logan County. Named in honor of R.O. Phillips, secretary of the Lincoln Land Company, which sold farmsteads in the area. 4,512 688.30 sq mi
(1,783 km2)
State map highlighting Phillips County


Pitkin County 097 Aspen 1881-02-23 Split from Gunnison County. Named in honor of Frederick Walker Pitkin, the second Governor of the State of Colorado. 17,348 970.37 sq mi
(2,513 km2)
State map highlighting Pitkin County


Prowers County 099 Lamar 1889-04-11 Split from Bent County. Named in honor of John W. Prowers, a pioneer of the Arkansas River valley. 11,996 1,645.37 sq mi
(4,261 km2)
State map highlighting Prowers County


Pueblo County 101 Pueblo 1861-11-01 Created as one of the 17 original counties of the Territory of Colorado. Named for historic town of Pueblo. Pueblo is a Spanish word meaning village or people. 169,622 2,396.77 sq mi
(6,208 km2)
State map highlighting Pueblo County


Rio Blanco County 103 Meeker 1889-03-25 Split from Garfield County. Named for the White River, which was originally named Rio Blanco in Spanish. 6,476 3,226.24 sq mi
(8,356 km2)
State map highlighting Rio Blanco County


Rio Grande County 105 Del Norte 1874-02-10 Split from Costilla County and Conejos County counties. Named for the Rio Grande, which flows through the area. 11,408 913.10 sq mi
(2,365 km2)
State map highlighting Rio Grande County


Routt County 107 Steamboat Springs 1877-01-29 Split from Grand County. Named in honor of John Long Routt, the first Governor of the State of Colorado. 25,091 2,362.11 sq mi
(6,118 km2)
State map highlighting Routt County


Saguache County 109 Saguache 1866-12-29 Split from Lake and Costilla counties. Name comes from a Ute language noun meaning "sand dunes".[b][9] 6,471 3,168.32 sq mi
(8,206 km2)
State map highlighting Saguache County


San Juan County 111 Silverton 1876-01-31 Split from Lake County. Named for the San Juan River and San Juan Mountains, which in turn were named for Saint John the Evangelist. 733 388.99 sq mi
(1,007 km2)
State map highlighting San Juan County


San Miguel County 113 Telluride 1883-03-02 Split from San Juan County. Named for the San Miguel River and San Miguel Mountains, which in turn were named for Saint Michael the Archangel. 8,074 1,290.76 sq mi
(3,343 km2)
State map highlighting San Miguel County


Sedgwick County 115 Julesburg 1889-04-09 Split from Logan County. Named for Fort Sedgwick, which, in turn, was named for U.S. Army General John Sedgwick (1813 - 1864). 2,336 548.83 sq mi
(1,421 km2)
State map highlighting Sedgwick County


Summit County 117 Breckenridge 1861-11-01 Created as one of the 17 original counties of the Territory of Colorado. Named for the many high mountain summits in the area. 30,941 618.92 sq mi
(1,603 km2)
State map highlighting Summit County


Teller County 119 Cripple Creek 1899-03-23 Split from El Paso and Fremont counties. Named in honor of Henry Moore Teller, a U.S. Senator from Colorado and United States Secretary of the Interior. 24,926 558.58 sq mi
(1,447 km2)
State map highlighting Teller County


Washington County 121 Akron 1887-02-09 Split from Weld County. Named in honor of George Washington (1732 - 1799), the first President of the United States. 4,861 2,522.90 sq mi
(6,534 km2)
State map highlighting Washington County


Weld County 123 Greeley 1861-11-01 Created as one of the 17 original counties of the Territory of Colorado. Named in honor of Lewis Ledyard Weld, the first Secretary of the Territory of Colorado. 340,036 4,013.84 sq mi
(10,396 km2)
State map highlighting Weld County


Yuma County 125 Wray 1889-03-15 Split from Washington County. Named for the Quechan (Yuma) Nation of Native Americans. 9,941 2,369.61 sq mi
(6,137 km2)
State map highlighting Yuma County

Notes

  1. ^ The ANSI INCITS 31:2009 county code is the five-digit code which uniquely identifies counties and county equivalents in the United States. The three-digit number is unique to each individual county within a state, but to be unique within the entire United States, it must be prefixed by the two-digit ANSI INCITS 31:2009 state code. This means that, for example, while Adams County, Colorado is 001, Belknap County, New Hampshire and Alachua County, Florida are also 001. To uniquely identify Adams County, Colorado, one must use the state code of 08 plus the county code of 001; therefore, the unique nationwide identifier for Adams County, Colorado is 08001. The links in the column INCITS are to the Census Bureau Info page for that county.
  2. ^ The name "Saguache" is pronounced /səˈwæ/. This name comes from the Ute language noun "sawup" /səˈwʌp/ meaning "sand dunes". The Spanish language version of this name is usually spelled "Saguache", while the English language version is usually spelled "Sawatch".

County data

The 64 Counties of the State of Colorado

2020 rank[10] County[11] County seat[11] Date established[11] CDOT map Population[10] 2020 density[a] Area[b] Elevation[c] Coordinates[d]
2020 Census Change 2010 Census Change 2000 Census Land Water Total Min[e] Max[f]
5 Adams County Brighton November 15, 1902 map 519,572 +17.66% 441,603 +26.87% 348,076 445 mi−2
172 km−2
1,166.7 mi2
3,021.8 km2
16.9 mi2
43.7 km2
1,183.6 mi2
3,065.5 km2
4,432 ft
1351 m
5,668 ft
1728 m
39°52′27″N 104°20′16″W / 39.8741789°N 104.3378450°W / 39.8741789; -104.3378450 (Adams County, Colorado)
31 Alamosa County Alamosa March 8, 1913 map 16,376 +6.03% 15,445 +3.21% 14,965 22.66 mi−2
8.75 km−2
722.6 mi2
1,871.6 km2
0.6 mi2
1.7 km2
723.2 mi2
1,873.3 km2
6,387 ft
1947 m
14,351 ft
4374 m
37°34′22″N 105°47′18″W / 37.5728342°N 105.7884000°W / 37.5728342; -105.7884000 (Alamosa County, Colorado)
3 Arapahoe County Littleton November 1, 1861 map 655,070 +14.52% 572,003 +17.01% 488,829 821 mi−2
317 km−2
797.9 mi2
2,066.4 km2
7.6 mi2
19.8 km2
805.5 mi2
2,086.2 km2
4,730 ft
1442 m
6,218 ft
1895 m
39°39′01″N 104°20′22″W / 39.6503229°N 104.3393175°W / 39.6503229; -104.3393175 (Arapahoe County, Colorado)
34 Archuleta County Pagosa Springs April 14, 1885 map 13,359 +10.55% 12,084 +22.13% 9,894 9.89 mi−2
3.82 km−2
1,350.1 mi2
3,496.7 km2
5.3 mi2
13.7 km2
1,355.4 mi2
3,510.4 km2
6,085 ft
1855 m
13,308 ft
4056 m
37°11′37″N 107°02′53″W / 37.1937061°N 107.0481382°W / 37.1937061; -107.0481382 (Archuleta County, Colorado)
55 Baca County Springfield April 16, 1889 map 3,506 −7.44% 3,788 −16.14% 4,517 1.37 mi−2
0.53 km−2
2,555.0 mi2
6,617.4 km2
2.4 mi2
6.1 km2
2,557.4 mi2
6,623.5 km2
3,458 ft
1054 m
5,293 ft
1613 m
37°19′09″N 102°33′38″W / 37.3191050°N 102.5604802°W / 37.3191050; -102.5604802 (Baca County, Colorado)
50 Bent County Las Animas February 11, 1870 map 5,650 −13.06% 6,499 +8.39% 5,996 3.73 mi−2
1.44 km−2
1,512.8 mi2
3,918.3 km2
28.2 mi2
73.1 km2
1,541.0 mi2
3,991.4 km2
3,671 ft
1119 m
4,857 ft
1481 m
37°57′17″N 103°04′18″W / 37.9548094°N 103.0717149°W / 37.9548094; -103.0717149 (Bent County, Colorado)
8 Boulder County Boulder November 1, 1861 map 330,758 +12.29% 294,567 +9.19% 269,784 455 mi−2
176 km−2
726.4 mi2
1,881.3 km2
14.1 mi2
36.5 km2
740.5 mi2
1,917.8 km2
4,717 ft
1438 m
14,259 ft
4346 m
40°05′33″N 105°21′28″W / 40.0924576°N 105.3577120°W / 40.0924576; -105.3577120 (Boulder County, Colorado)
12 City and County of Broomfield Broomfield November 15, 2001 map 74,112 +32.61% 55,889 +42.57% 39,202 2,248 mi−2
868 km−2
33.0 mi2
85.4 km2
0.6 mi2
1.5 km2
33.6 mi2
86.9 km2
4,691 ft
1430 m
5,848 ft
1783 m
39°57′15″N 105°03′10″W / 39.9541268°N 105.0527103°W / 39.9541268; -105.0527103 (City and County of Broomfield, Colorado)
26 Chaffee County Salida February 10, 1879 map 19,476 +9.36% 17,809 +9.59% 16,250 19.22 mi−2
7.42 km−2
1,013.4 mi2
2,624.7 km2
1.5 mi2
4.0 km2
1,014.9 mi2
2,628.7 km2
5,298 ft
1615 m
14,427 ft
4397 m
38°44′48″N 106°11′38″W / 38.7465981°N 106.1937627°W / 38.7465981; -106.1937627 (Chaffee County, Colorado)
59 Cheyenne County Cheyenne Wells March 25, 1889 map 1,748 −4.79% 1,836 −17.63% 2,229 0.98 mi−2
0.38 km−2
1,778.3 mi2
4,605.7 km2
3.2 mi2
8.2 km2
1,781.5 mi2
4,613.9 km2
3,740 ft
1140 m
5,257 ft
1602 m
38°49′41″N 102°36′12″W / 38.8281780°N 102.6034141°W / 38.8281780; -102.6034141 (Cheyenne County, Colorado)
39 Clear Creek County Georgetown November 1, 1861 map 9,397 +3.40% 9,088 −1.89% 9,263 23.79 mi−2
9.18 km−2
395.1 mi2
1,023.2 km2
1.3 mi2
3.3 km2
396.4 mi2
1,026.5 km2
5,075 ft
1547 m
14,278 ft
4352 m
39°41′21″N 105°38′40″W / 39.6890622°N 105.6443074°W / 39.6890622; -105.6443074 (Clear Creek County, Colorado)
41 Conejos County Conejos November 7, 1861 map 7,461 −9.63% 8,256 −1.71% 8,400 5.80 mi−2
2.24 km−2
1,287.4 mi2
3,334.4 km2
3.6 mi2
9.2 km2
1,291.0 mi2
3,343.6 km2
7,404 ft
2257 m
13,179 ft
4017 m
37°12′03″N 106°11′29″W / 37.2007929°N 106.1914806°W / 37.2007929; -106.1914806 (Conejos County, Colorado)
56 Costilla County San Luis November 1, 1861 map 3,499 −0.71% 3,524 −3.74% 3,661 2.85 mi−2
1.10 km−2
1,227.6 mi2
3,179.5 km2
3.4 mi2
8.8 km2
1,231.0 mi2
3,188.3 km2
7,375 ft
2248 m
14,351 ft
4374 m
37°16′40″N 105°25′42″W / 37.2776823°N 105.4283908°W / 37.2776823; -105.4283908 (Costilla County, Colorado)
47 Crowley County Ordway May 29, 1911 map 5,922 +1.70% 5,823 +5.60% 5,514 7.52 mi−2
2.90 km−2
787.4 mi2
2,039.4 km2
12.9 mi2
33.4 km2
800.3 mi2
2,072.8 km2
3,966 ft
1209 m
5,228 ft
1593 m
38°19′36″N 103°47′05″W / 38.3265917°N 103.7848382°W / 38.3265917; -103.7848382 (Crowley County, Colorado)
53 Custer County Westcliffe March 9, 1877 map 4,704 +10.55% 4,255 +21.29% 3,508 6.37 mi−2
2.46 km−2
738.6 mi2
1,913.0 km2
1.3 mi2
3.4 km2
739.9 mi2
1,916.4 km2
4,547 ft
1386 m
14,246 ft
4342 m
38°06′31″N 105°22′03″W / 38.1086939°N 105.3674060°W / 38.1086939; -105.3674060 (Custer County, Colorado)
18 Delta County Delta February 11, 1883 map 31,196 +0.79% 30,952 +11.24% 27,824 27.3 mi−2
10.5 km−2
1,142.1 mi2
2,958.1 km2
6.5 mi2
16.8 km2
1,148.6 mi2
2,974.9 km2
4,763 ft
1452 m
11,396 ft
3474 m
38°51′41″N 107°51′48″W / 38.8613998°N 107.8631974°W / 38.8613998; -107.8631974 (Delta County, Colorado)
2 City and County of Denver Denver December 1, 1902 map 715,522 +19.22% 600,158 +8.37% 553,805 4,674 mi−2
1,805 km−2
153.1 mi2
396.5 km2
1.7 mi2
4.3 km2
154.8 mi2
400.8 km2
4,803 ft
1464 m
5,688 ft
1734 m
39°45′43″N 104°52′34″W / 39.7619809°N 104.8760040°W / 39.7619809; -104.8760040 (City and County of Denver, Colorado)
58 Dolores County Dove Creek March 4, 1881 map 2,326 +12.69% 2,064 +11.93% 1,844 2.18 mi−2
0.84 km−2
1,067.2 mi2
2,764.0 km2
1.0 mi2
2.7 km2
1,068.2 mi2
2,766.7 km2
4,911 ft
1497 m
14,252 ft
4344 m
37°45′07″N 108°31′02″W / 37.7519785°N 108.5173060°W / 37.7519785; -108.5173060 (Dolores County, Colorado)
7 Douglas County Castle Rock November 1, 1861 map 357,978 +25.40% 285,465 +62.44% 175,732 426 mi−2
164 km−2
840.2 mi2
2,176.2 km2
2.6 mi2
6.8 km2
842.8 mi2
2,183.0 km2
5,242 ft
1598 m
9,836 ft
2998 m
39°19′47″N 104°55′47″W / 39.3296108°N 104.9297053°W / 39.3296108; -104.9297053 (Douglas County, Colorado)
14 Eagle County Eagle February 11, 1883 map 55,731 +6.77% 52,197 +25.40% 41,623 33.1 mi−2
12.8 km−2
1,684.5 mi2
4,362.8 km2
7.3 mi2
19.0 km2
1,691.8 mi2
4,381.8 km2
6,220 ft
1896 m
14,011 ft
4271 m
39°37′40″N 106°41′43″W / 39.6277366°N 106.6951442°W / 39.6277366; -106.6951442 (Eagle County, Colorado)
1 El Paso County Colorado Springs November 1, 1861 map 730,395 +17.38% 622,263 +20.38% 516,934 343 mi−2
133 km−2
2,126.4 mi2
5,507.4 km2
2.7 mi2
7.1 km2
2,129.1 mi2
5,514.5 km2
5,055 ft
1541 m
14,115 ft
4302 m
38°49′55″N 104°31′31″W / 38.8320014°N 104.5253965°W / 38.8320014; -104.5253965 (El Paso County, Colorado)
21 Elbert County Kiowa February 2, 1874 map 26,062 +12.89% 23,086 +16.27% 19,855 14.08 mi−2
5.44 km−2
1,850.8 mi2
4,793.6 km2
0.2 mi2
0.4 km2
1,851.0 mi2
4,794.0 km2
4,580 ft
1396 m
7,374 ft
2248 m
39°17′11″N 104°08′08″W / 39.2864464°N 104.1354658°W / 39.2864464; -104.1354658 (Elbert County, Colorado)
16 Fremont County Cañon City November 1, 1861 map 48,939 +4.52% 46,824 +1.48% 46,140 31.9 mi−2
12.3 km−2
1,533.9 mi2
3,972.7 km2
0.9 mi2
2.2 km2
1,534.8 mi2
3,974.9 km2
4,573 ft
1394 m
13,110 ft
3996 m
38°28′24″N 105°26′22″W / 38.4732142°N 105.4394323°W / 38.4732142; -105.4394323 (Fremont County, Colorado)
13 Garfield County Glenwood Springs February 10, 1883 map 61,685 +9.39% 56,389 +28.78% 43,786 20.93 mi−2
8.08 km−2
2,947.4 mi2
7,633.8 km2
8.4 mi2
21.7 km2
2,955.8 mi2
7,655.5 km2
4,471 ft
1363 m
12,361 ft
3768 m
39°36′01″N 107°54′19″W / 39.6003285°N 107.9052109°W / 39.6003285; -107.9052109 (Garfield County, Colorado)
48 Gilpin County Central City November 1, 1861 map 5,808 +6.75% 5,441 +14.64% 4,746 38.7 mi−2
14.9 km−2
150.0 mi2
388.6 km2
0.4 mi2
0.9 km2
150.4 mi2
389.5 km2
4,983 ft
1519 m
13,300 ft
4054 m
39°51′27″N 105°31′21″W / 39.8575395°N 105.5225847°W / 39.8575395; -105.5225847 (Gilpin County, Colorado)
32 Grand County Hot Sulphur Springs February 2, 1874 map 15,717 +5.89% 14,843 +19.38% 12,433 8.51 mi−2
3.29 km−2
1,846.4 mi2
4,782.3 km2
23.1 mi2
59.9 km2
1,869.5 mi2
4,842.2 km2
6,040 ft
1841 m
13,559 ft
4133 m
40°06′09″N 106°07′05″W / 40.1025426°N 106.1181476°W / 40.1025426; -106.1181476 (Grand County, Colorado)
30 Gunnison County Gunnison March 9, 1877 map 16,918 +10.40% 15,324 +9.46% 14,000 5.22 mi−2
2.02 km−2
3,239.1 mi2
8,389.3 km2
20.5 mi2
53.1 km2
3,259.6 mi2
8,442.4 km2
7,178 ft
2188 m
14,279 ft
4352 m
38°39′59″N 107°01′55″W / 38.6663669°N 107.0318806°W / 38.6663669; -107.0318806 (Gunnison County, Colorado)
63 Hinsdale County Lake City February 10, 1874 map 788 −6.52% 843 +6.44% 792 0.71 mi−2
0.27 km−2
1,117.2 mi2
2,893.6 km2
5.9 mi2
15.3 km2
1,123.1 mi2
2,908.9 km2
7,299 ft
2225 m
14,321 ft
4365 m
37°49′15″N 107°18′01″W / 37.8208029°N 107.3003634°W / 37.8208029; -107.3003634 (Hinsdale County, Colorado)
44 Huerfano County Walsenburg November 1, 1861 map 6,820 +1.62% 6,711 −14.61% 7,859 4.29 mi−2
1.66 km−2
1,591.0 mi2
4,120.8 km2
2.2 mi2
5.8 km2
1,593.2 mi2
4,126.6 km2
4,445 ft
1355 m
14,326 ft
4366 m
37°41′05″N 104°57′38″W / 37.6846648°N 104.9605114°W / 37.6846648; -104.9605114 (Huerfano County, Colorado)
61 Jackson County Walden May 5, 1909 map 1,379 −1.08% 1,394 −11.60% 1,577 0.85 mi−2
0.33 km−2
1,613.7 mi2
4,179.5 km2
7.2 mi2
18.8 km2
1,620.9 mi2
4,198.3 km2
4,865 ft
1483 m
12,954 ft
3948 m
40°39′58″N 106°20′32″W / 40.6661359°N 106.3423570°W / 40.6661359; -106.3423570 (Jackson County, Colorado)
4 Jefferson County Golden November 1, 1861 map 582,910 +9.05% 534,543 +1.73% 525,449 763 mi−2
294 km−2
764.4 mi2
1,979.7 km2
9.7 mi2
25.1 km2
774.1 mi2
2,004.8 km2
4,986 ft
1520 m
11,589 ft
3532 m
39°35′09″N 105°15′02″W / 39.5858881°N 105.2506412°W / 39.5858881; -105.2506412 (Jefferson County, Colorado)
60 Kiowa County Eads April 11, 1889 map 1,446 +3.43% 1,398 −13.81% 1,622 0.82 mi−2
0.32 km−2
1,767.8 mi2
4,578.6 km2
18.2 mi2
47.0 km2
1,786.0 mi2
4,625.6 km2
3,687 ft
1124 m
4,697 ft
1432 m
38°26′00″N 102°44′26″W / 38.4332694°N 102.7404800°W / 38.4332694; -102.7404800 (Kiowa County, Colorado)
43 Kit Carson County Burlington April 11, 1889 map 7,087 −14.30% 8,270 +3.21% 8,013 3.28 mi−2
1.27 km−2
2,160.8 mi2
5,596.5 km2
0.9 mi2
2.3 km2
2,161.7 mi2
5,598.8 km2
3,523 ft
1074 m
5,297 ft
1615 m
39°18′20″N 102°36′10″W / 39.3055557°N 102.6029123°W / 39.3055557; -102.6029123 (Kit Carson County, Colorado)
15 La Plata County Durango February 10, 1874 map 55,638 +8.38% 51,334 +16.78% 43,957 32.9 mi−2
12.7 km−2
1,689.7 mi2
4,376.3 km2
9.9 mi2
25.6 km2
1,699.6 mi2
4,401.9 km2
4,268 ft
1301 m
14,093 ft
4296 m
37°17′11″N 107°50′37″W / 37.2863619°N 107.8435620°W / 37.2863619; -107.8435620 (La Plata County, Colorado)
42 Lake County Leadville November 1, 1861 map 7,436 +1.72% 7,310 −6.45% 7,814 19.73 mi−2
7.62 km−2
376.9 mi2
976.2 km2
7.0 mi2
18.1 km2
383.9 mi2
994.3 km2
8,720 ft
2658 m
14,440 ft
4401 m
39°12′08″N 106°20′42″W / 39.2023129°N 106.3449111°W / 39.2023129; -106.3449111 (Lake County, Colorado)
6 Larimer County Fort Collins November 1, 1861 map 359,066 +19.84% 299,630 +19.14% 251,494 138.3 mi−2
53.4 km−2
2,595.8 mi2
6,723.0 km2
38.2 mi2
99.0 km2
2,634.0 mi2
6,822.0 km2
4,557 ft
1389 m
13,573 ft
4137 m
40°39′58″N 105°27′39″W / 40.6661903°N 105.4607444°W / 40.6661903; -105.4607444 (Larimer County, Colorado)
33 Las Animas County Trinidad February 9, 1866 map 14,555 −6.14% 15,507 +1.94% 15,212 3.05 mi−2
1.18 km−2
4,772.9 mi2
12,361.9 km2
2.7 mi2
6.9 km2
4,775.6 mi2
12,368.8 km2
4,317 ft
1316 m
13,631 ft
4155 m
37°19′00″N 104°02′21″W / 37.3166220°N 104.0391104°W / 37.3166220; -104.0391104 (Las Animas County, Colorado)
49 Lincoln County Hugo April 11, 1889 map 5,675 +3.80% 5,467 −10.22% 6,089 2.20 mi−2
0.85 km−2
2,577.7 mi2
6,676.2 km2
8.8 mi2
22.8 km2
2,586.5 mi2
6,699.0 km2
3,923 ft
1196 m
5,973 ft
1821 m
38°59′13″N 103°30′53″W / 38.9869846°N 103.5146043°W / 38.9869846; -103.5146043 (Lincoln County, Colorado)
25 Logan County Sterling February 25, 1887 map 21,528 −5.20% 22,709 +10.42% 20,566 11.71 mi−2
4.52 km−2
1,838.6 mi2
4,761.9 km2
6.3 mi2
16.4 km2
1,844.9 mi2
4,778.3 km2
3,428 ft
1045 m
4,947 ft
1508 m
40°43′29″N 103°06′36″W / 40.7245834°N 103.1100639°W / 40.7245834; -103.1100639 (Logan County, Colorado)
11 Mesa County Grand Junction February 14, 1883 map 155,703 +6.12% 146,723 +25.47% 116,939 46.8 mi−2
18.1 km−2
3,328.7 mi2
8,621.3 km2
12.4 mi2
32.0 km2
3,341.1 mi2
8,653.3 km2
4,337 ft
1322 m
11,236 ft
3425 m
39°01′05″N 108°28′04″W / 39.0181664°N 108.4677131°W / 39.0181664; -108.4677131 (Mesa County, Colorado)
62 Mineral County Creede March 27, 1893 map 865 +21.49% 712 −14.32% 831 0.99 mi−2
0.38 km−2
875.8 mi2
2,268.2 km2
2.0 mi2
5.2 km2
877.8 mi2
2,273.4 km2
7,549 ft
2301 m
13,902 ft
4237 m
37°40′07″N 106°55′27″W / 37.6687329°N 106.9240618°W / 37.6687329; -106.9240618 (Mineral County, Colorado)
35 Moffat County Craig February 27, 1911 map 13,292 −3.65% 13,795 +4.68% 13,178 2.80 mi−2
1.08 km−2
4,743.2 mi2
12,284.9 km2
7.6 mi2
19.8 km2
4,750.8 mi2
12,304.7 km2
4,993 ft
1522 m
10,840 ft
3304 m
40°37′07″N 108°12′27″W / 40.6187129°N 108.2074659°W / 40.6187129; -108.2074659 (Moffat County, Colorado)
22 Montezuma County Cortez April 16, 1889 map 25,849 +1.23% 25,535 +7.19% 23,822 12.74 mi−2
4.92 km−2
2,029.3 mi2
5,256.0 km2
10.5 mi2
27.2 km2
2,039.8 mi2
5,283.2 km2
4,639 ft
1414 m
13,237 ft
4035 m
37°20′18″N 108°35′49″W / 37.3383013°N 108.5970269°W / 37.3383013; -108.5970269 (Montezuma County, Colorado)
17 Montrose County Montrose February 11, 1883 map 42,679 +3.40% 41,276 +23.44% 33,438 19.05 mi−2
7.35 km−2
2,240.9 mi2
5,804.0 km2
1.9 mi2
4.9 km2
2,242.8 mi2
5,808.9 km2
4,711 ft
1436 m
11,453 ft
3491 m
38°24′10″N 108°16′13″W / 38.4026876°N 108.2701893°W / 38.4026876; -108.2701893 (Montrose County, Colorado)
20 Morgan County Fort Morgan February 19, 1889 map 29,111 +3.38% 28,159 +3.63% 27,172 22.73 mi−2
8.78 km−2
1,280.5 mi2
3,316.4 km2
13.4 mi2
34.7 km2
1,293.9 mi2
3,351.1 km2
3,989 ft
1216 m
4,937 ft
1505 m
40°15′45″N 103°48′35″W / 40.2625815°N 103.8098295°W / 40.2625815; -103.8098295 (Morgan County, Colorado)
27 Otero County La Junta March 25, 1889 map 18,690 −0.75% 18,831 −7.29% 20,311 14.81 mi−2
5.72 km−2
1,261.9 mi2
3,268.4 km2
7.8 mi2
20.1 km2
1,269.7 mi2
3,288.5 km2
3,809 ft
1161 m
5,273 ft
1607 m
37°54′09″N 103°43′00″W / 37.9025553°N 103.7165564°W / 37.9025553; -103.7165564 (Otero County, Colorado)
51 Ouray County Ouray January 18, 1877 map 4,874 +9.87% 4,436 +18.39% 3,747 9.01 mi−2
3.48 km−2
540.7 mi2
1,400.3 km2
1.5 mi2
4.0 km2
542.2 mi2
1,404.3 km2
6,315 ft
1925 m
14,158 ft
4315 m
38°09′19″N 107°46′09″W / 38.1553962°N 107.7691411°W / 38.1553962; -107.7691411 (Ouray County, Colorado)
28 Park County Fairplay November 1, 1861 map 17,390 +7.31% 16,206 +11.62% 14,519 7.93 mi−2
3.06 km−2
2,193.5 mi2
5,681.2 km2
16.8 mi2
43.5 km2
2,210.3 mi2
5,724.7 km2
5,826 ft
1776 m
14,293 ft
4357 m
39°07′08″N 105°43′02″W / 39.1187954°N 105.7171190°W / 39.1187954; -105.7171190 (Park County, Colorado)
54 Phillips County Holyoke March 27, 1889 map 4,530 +1.98% 4,442 −0.96% 4,485 6.59 mi−2
2.54 km−2
687.9 mi2
1,781.7 km2
0.1 mi2
0.3 km2
688.0 mi2
1,782.0 km2
3,582 ft
1092 m
4,117 ft
1255 m
40°35′38″N 102°21′27″W / 40.5939029°N 102.3575846°W / 40.5939029; -102.3575846 (Phillips County, Colorado)
29 Pitkin County Aspen February 23, 1881 map 17,358 +1.22% 17,148 +15.17% 14,889 17.88 mi−2
6.90 km−2
970.7 mi2
2,514.1 km2
2.5 mi2
6.5 km2
973.2 mi2
2,520.6 km2
5,695 ft
1736 m
14,279 ft
4352 m
39°13′02″N 106°54′59″W / 39.2172422°N 106.9164625°W / 39.2172422; -106.9164625 (Pitkin County, Colorado)
36 Prowers County Lamar April 11, 1889 map 11,999 −4.40% 12,551 −13.34% 14,483 7.32 mi−2
2.83 km−2
1,638.4 mi2
4,243.5 km2
5.9 mi2
15.3 km2
1,644.3 mi2
4,258.8 km2
3,346 ft
1020 m
4,713 ft
1437 m
37°57′18″N 102°23′36″W / 37.9549242°N 102.3933533°W / 37.9549242; -102.3933533 (Prowers County, Colorado)
10 Pueblo County Pueblo November 1, 1861 map 168,162 +5.72% 159,063 +12.42% 141,490 70.5 mi−2
27.2 km−2
2,386.6 mi2
6,181.2 km2
11.2 mi2
28.9 km2
2,397.8 mi2
6,210.1 km2
4,291 ft
1308 m
12,352 ft
3765 m
38°10′24″N 104°30′46″W / 38.1732322°N 104.5127765°W / 38.1732322; -104.5127765 (Pueblo County, Colorado)
45 Rio Blanco County Meeker March 25, 1889 map 6,529 −2.06% 6,666 +11.25% 5,992 2.03 mi−2
0.78 km−2
3,221.0 mi2
8,342.3 km2
1.9 mi2
4.9 km2
3,222.9 mi2
8,347.2 km2
5,062 ft
1543 m
12,033 ft
3668 m
39°58′50″N 108°13′05″W / 39.9806725°N 108.2179271°W / 39.9806725; -108.2179271 (Rio Blanco County, Colorado)
37 Rio Grande County Del Norte February 10, 1874 map 11,539 −3.70% 11,982 −3.57% 12,425 12.65 mi−2
4.89 km−2
912.0 mi2
2,362.0 km2
0.4 mi2
1.0 km2
912.4 mi2
2,363.0 km2
7,467 ft
2276 m
13,209 ft
4026 m
37°34′57″N 106°22′59″W / 37.5825367°N 106.3831577°W / 37.5825367; -106.3831577 (Rio Grande County, Colorado)
23 Routt County Steamboat Springs January 29, 1877 map 24,829 +5.61% 23,509 +19.46% 19,679 10.51 mi−2
4.06 km−2
2,362.0 mi2
6,117.6 km2
6.1 mi2
15.8 km2
2,368.1 mi2
6,133.4 km2
6,266 ft
1910 m
12,185 ft
3714 m
40°29′03″N 106°59′27″W / 40.4840785°N 106.9907816°W / 40.4840785; -106.9907816 (Routt County, Colorado)
46 Saguache County Saguache December 29, 1866 map 6,368 +4.26% 6,108 +3.46% 5,904 2.01 mi−2
0.78 km−2
3,168.6 mi2
8,206.5 km2
1.7 mi2
4.5 km2
3,170.3 mi2
8,211.0 km2
6,013 ft
1833 m
14,300 ft
4359 m
38°04′51″N 106°16′51″W / 38.0807339°N 106.2808607°W / 38.0807339; -106.2808607 (Saguache County, Colorado)
64 San Juan County Silverton January 31, 1876 map 705 +0.86% 699 +25.27% 558 1.82 mi−2
0.70 km−2
387.5 mi2
1,003.7 km2
0.8 mi2
2.0 km2
388.3 mi2
1,005.7 km2
7,683 ft
2342 m
13,900 ft
4237 m
37°45′50″N 107°40′34″W / 37.7640122°N 107.6762274°W / 37.7640122; -107.6762274 (San Juan County, Colorado)
40 San Miguel County Telluride March 2, 1883 map 8,072 +9.69% 7,359 +11.62% 6,593 6.27 mi−2
2.42 km−2
1,286.7 mi2
3,332.6 km2
2.0 mi2
5.2 km2
1,288.7 mi2
3,337.8 km2
5,308 ft
1618 m
14,023 ft
4274 m
38°00′15″N 108°24′21″W / 38.0042019°N 108.4057022°W / 38.0042019; -108.4057022 (San Miguel County, Colorado)
57 Sedgwick County Julesburg April 9, 1889 map 2,404 +1.05% 2,379 −13.40% 2,747 4.39 mi−2
1.69 km−2
548.0 mi2
1,419.4 km2
1.4 mi2
3.5 km2
549.4 mi2
1,422.9 km2
3,477 ft
1060 m
4,127 ft
1258 m
40°52′33″N 102°21′06″W / 40.8759564°N 102.3517903°W / 40.8759564; -102.3517903 (Sedgwick County, Colorado)
19 Summit County Breckenridge November 1, 1861 map 31,055 +10.93% 27,994 +18.82% 23,560 51.0 mi−2
19.7 km−2
608.3 mi2
1,575.6 km2
10.9 mi2
28.3 km2
619.2 mi2
1,603.9 km2
7,460 ft
2274 m
14,278 ft
4352 m
39°38′02″N 106°06′58″W / 39.6339611°N 106.1160413°W / 39.6339611; -106.1160413 (Summit County, Colorado)
24 Teller County Cripple Creek March 23, 1899 map 24,710 +5.82% 23,350 +13.68% 20,541 44.4 mi−2
17.1 km−2
557.1 mi2
1,442.8 km2
1.9 mi2
5.0 km2
559.0 mi2
1,447.8 km2
5,236 ft
1596 m
13,065 ft
3982 m
38°52′56″N 105°09′42″W / 38.8821769°N 105.1617222°W / 38.8821769; -105.1617222 (Teller County, Colorado)
52 Washington County Akron February 9, 1887 map 4,817 +0.06% 4,814 −2.19% 4,922 1.91 mi−2
0.74 km−2
2,518.1 mi2
6,521.8 km2
5.9 mi2
15.2 km2
2,524.0 mi2
6,537.0 km2
3,910 ft
1192 m
5,433 ft
1656 m
39°58′14″N 103°12′06″W / 39.9704267°N 103.2016452°W / 39.9704267; -103.2016452 (Washington County, Colorado)
9 Weld County Greeley November 1, 1861 map 328,981 +30.12% 252,825 +39.86% 180,766 82.6 mi−2
31.9 km−2
3,984.9 mi2
10,321.0 km2
31.8 mi2
82.4 km2
4,016.7 mi2
10,403.4 km2
3,959 ft
1207 m
6,388 ft
1947 m
40°33′15″N 104°23′38″W / 40.5542451°N 104.3937513°W / 40.5542451; -104.3937513 (Weld County, Colorado)
38 Yuma County Wray March 15, 1889 map 9,988 −0.55% 10,043 +2.00% 9,846 4.22 mi−2
1.63 km−2
2,364.4 mi2
6,123.8 km2
4.3 mi2
11.1 km2
2,368.7 mi2
6,134.9 km2
3,317 ft
1011 m
4,447 ft
1355 m
40°00′08″N 102°25′27″W / 40.0022004°N 102.4242526°W / 40.0022004; -102.4242526 (Yuma County, Colorado)
State Colorado Denver August 1, 1876 map 5,773,714 +14.80% 5,029,196 +16.92% 4,301,262 55.7 mi−2
21.5 km−2
103,641.9 mi2
268,431.2 km2
451.8 mi2
1,170.1 km2
104,093.7 mi2
269,601.3 km2
3,317 ft
1011 m
14,440 ft
4401 m
38°59′50″N 105°32′52″W / 38.9972°N 105.5478°W / 38.9972; -105.5478 (State of Colorado)

Notes

  1. ^ The population density per land area at the 2020 Census.[10][12]
  2. ^ The area of the county as determined by the United States Census Bureau.[12]
  3. ^ Elevations include an adjustment from the National Geodetic Vertical Datum of 1929 (NGVD 29) to the North American Vertical Datum of 1988 (NAVD 88).
  4. ^ The centroid coordinates of the county as determined by the United States Census Bureau.[12]
  5. ^ The minimum elevation in the county. Only a few of these county low points have been verified.
  6. ^ The maximum elevation in the county.[13] See the List of Colorado county high points.

County high points

Main article: List of Colorado county high points

Former counties

The following sortable table lists all the historic counties of the Territory of New Mexico, the Territory of Utah, the Territory of Kansas, and the extralegal Territory of Jefferson[14] that previously existed within the boundaries of the present State of Colorado, as well as the three defunct counties of the Territory of Colorado and the three defunct counties of the State of Colorado.[a]

Counties formerly within the area of the State of Colorado

County Territory or State Date created Date superseded History
Taos County Territory of New Mexico 1852-01-09 1861-02-28 Originally one of the seven partidos of the Spanish, and later Mexican, province of Santa Fe de Nuevo México. One of the nine original counties created by the Territory of New Mexico in 1852. Excluded from the new Territory of Colorado in 1861.
Great Salt Lake County Territory of Utah 1852-03-03 1861-02-28 Created in 1852. Excluded from the new Territory of Colorado in 1861.
Green River County Territory of Utah 1852-03-03 1861-02-28 Created in 1852, but never organized. Dissolved in 1857, but recreated in 1859. Excluded from the new Territory of Colorado in 1861, and the Territory of Wyoming in 1868. Finally dissolved in 1872.
Iron County Territory of Utah 1852-03-03 1861-02-28 Created in 1852. Excluded from the new Territory of Colorado in 1861.
Sanpete County Territory of Utah 1852-03-03 1861-02-28 Created in 1852. Excluded from the new Territory of Colorado in 1861.
Utah County Territory of Utah 1852-03-03 1861-02-28 Created in 1852. Excluded from the new Territory of Colorado in 1861.
Washington County Territory of Utah 1852-03-03 1861-02-28 Created in 1852. Excluded from the new Territory of Colorado in 1861.
Arapahoe County Territory of Kansas 1855-08-25 1861-01-29 Created in 1855, but never organized. Reverted to unorganized territory when Kansas joined the Union in 1861.
Beaver County Territory of Utah 1856-01-05 1861-02-28 Split from Iron and Millard counties in 1856. Excluded from the new Territory of Colorado in 1861.
Broderick County Territory of Kansas 1859-02-07 1861-01-29 Split from Arapahoe County in 1859, but never organized. Reverted to unorganized territory when Kansas joined the Union in 1861.
El Paso County Territory of Kansas 1859-02-07 1861-01-29 Split from Arapahoe County in 1859, but never organized. Reverted to unorganized territory when Kansas joined the Union in 1861.
Fremont County Territory of Kansas 1859-02-07 1861-01-29 Split from Arapahoe County in 1859, but never organized. Reverted to unorganized territory when Kansas joined the Union in 1861.
Montana County Territory of Kansas 1859-02-07 1861-01-29 Split from Arapahoe County in 1859, but never organized. Reverted to unorganized territory when Kansas joined the Union in 1861.
Oro County Territory of Kansas 1859-02-07 1861-01-29 Split from Arapahoe County in 1859, but never organized. Reverted to unorganized territory when Kansas joined the Union in 1861.
Peketon County Territory of Kansas 1859-02-07 1861-01-29 Created in 1859, but never organized. Reverted to unorganized territory when Kansas joined the Union in 1861.
Arrappahoe County Territory of Jefferson 1859-11-28 1861-02-28 One of the 12 counties created by the extralegal Territory of Jefferson in 1859.
Cheyenne County Territory of Jefferson 1859-11-28 1861-02-28 One of the 12 counties created by the extralegal Territory of Jefferson in 1859.
El Paso County Territory of Jefferson 1859-11-28 1861-02-28 One of the 12 counties created by the extralegal Territory of Jefferson in 1859.
Fountain County Territory of Jefferson 1859-11-28 1861-02-28 One of the 12 counties created by the extralegal Territory of Jefferson in 1859.
Heele County Territory of Jefferson 1859-11-28 1861-02-28 One of the 12 counties created by the extralegal Territory of Jefferson in 1859.
Jackson County Territory of Jefferson 1859-11-28 1861-02-28 One of the 12 counties created by the extralegal Territory of Jefferson in 1859.
Jefferson County Territory of Jefferson 1859-11-28 1861-02-28 One of the 12 counties created by the extralegal Territory of Jefferson in 1859.
Mountain County Territory of Jefferson 1859-11-28 1861-02-28 One of the 12 counties created by the extralegal Territory of Jefferson in 1859.
North County Territory of Jefferson 1859-11-28 1861-02-28 One of the 12 counties created by the extralegal Territory of Jefferson in 1859.
Park County Territory of Jefferson 1859-11-28 1861-02-28 One of the 12 counties created by the extralegal Territory of Jefferson in 1859.
St. Vrain County Territory of Jefferson 1859-11-28 1861-02-28 One of the 12 counties created by the extralegal Territory of Jefferson in 1859.
Saratoga County Territory of Jefferson 1859-11-28 1861-02-28 One of the 12 counties created by the extralegal Territory of Jefferson in 1859.
Mora County Territory of New Mexico 1860-02-01 1861-02-28 Split from Taos County and San Miguel County in 1860. Excluded from the new Territory of Colorado in 1861.
Guadalupe County Territory of Colorado 1861-11-01 1861-11-07 One of the 17 original counties created by the Territory of Colorado in 1861. The county was renamed Conejos County after only six days.
Greenwood County Territory of Colorado 1870-02-11 1874-02-06 Created from expropriated Cheyenne and Arapaho tribal land and the eastern portion of Huerfano County in 1870. The county was abolished in 1874 and its territory split between Elbert County and Bent County.
Platte County Territory of Colorado 1872-02-09 1874-02-09 Created from the eastern portion of Weld County in 1872. The county was abolished in 1874 after organizers failed to secure voter approval. The territory of the county was returned to Weld County.
Carbonate County State of Colorado 1879-02-08 1879-02-10 Lake County was renamed Carbonate County in 1879. Only two days later, Carbonate County was split into the new Chaffee County and a recreated Lake County.
Uncompahgre County State of Colorado 1883-02-27 1883-03-02 Ouray County was renamed Uncompahgre County for only four days in 1883.
South Arapahoe County State of Colorado 1902-11-15 1903-04-11 One of three counties created from Arapahoe County in 1902. The name was changed back to Arapahoe County after five months.

Note

  1. ^ No organized counties of the District of Louisiana, the Territory of Missouri, the extralegal State of Deseret, or the Territory of Nebraska existed within the present boundaries of the State of Colorado.

County distinctions

1. Costilla County was the first area within the present State of Colorado to be settled by Europeans in 1851.
2. Taos County, created by the Territory of New Mexico in 1852, was the first organized county to extend into the area of the present State of Colorado.
3. Arapahoe County, created by the Territory of Kansas in 1855, was the first county created exclusively within the area of the present State of Colorado.
4. On November 28, 1859, the extralegal Territory of Jefferson created 12 counties:[14]
The 12 counties of the
Territory of Jefferson
County County Seat
Arrappahoe County Denver City
Cheyenne County
El Paso County Colorado City
Fountain County Pueblo
Heele County La Porte
Jackson County Boulder City
Jefferson County Arapahoe City
Golden City
Mountain County Central City
North County
Park County Tarryall City
Saint Vrain's CountySt. Vrain's County Saint VrainSt. Vrain
Saratoga County Breckinridge
5. On November 1, 1861, the Territory of Colorado created the 17 original Colorado counties:
The 17 original counties of the
Territory of Colorado
County First County Seat
Arapahoe County Denver City
Boulder County Boulder City
Clear Creek County Idaho
Costilla County San Miguel
Douglas County Frankstown
El Paso County Colorado City
Fremont County Cañon City
Gilpin County Central City
Guadaloupe County Guadaloupe
Huerfano County Autobees Plaza
Jefferson County Golden City
Lake County Oro City
Larimer County La Porte
Park County Tarryall City
Pueblo County Pueblo
Summit County Parkville
Weld County Saint VrainSt. Vrain
6. Of the 17 original Colorado counties created in 1861, only Gilpin County and Clear Creek County have retained their original boundaries with only minor survey changes.
7. Guadaloupe County was the first Colorado county to be renamed after only six days in 1861.
8. Las Animas County was the first new Colorado county to be created (in 1866) after the original 17 counties.
9. Greenwood County was the longest lived former Colorado county, existing four years from 1870 to 1874.
10. In 1876, San Juan County became the last county created by the Territory of Colorado.
11. In 1877, Ouray County became the first county created by the new State of Colorado.
12. Carbonate County was the shortest lived former Colorado county, existing only two days in 1879 before being dissolved.
13. The City and County of Broomfield became the newest Colorado county in 2001.
14. Las Animas County is the most extensive Colorado county.
15. The City and County of Broomfield is the least extensive Colorado county.
16. El Paso County is the most populous Colorado county.
17. San Juan County is the least populous Colorado county.
18. The City and County of Denver is the most densely populated Colorado county.
19. Hinsdale County is the least densely populated Colorado county.
20. El Paso County and the City and County of Denver and are among the 100 most populous counties of the United States.
21. San Juan County, Hinsdale County, Mineral County, Jackson County, Kiowa County, and Cheyenne County are among the 100 least populous counties of the United States.
22. Lake County has the highest point in Colorado at the summit of Mount Elbert at an elevation of 14,440 feet (4,401.2 m), the highest summit of all the Rocky Mountains of North America.
23. Yuma County has the lowest point in Colorado where the Arikaree River flows into Kansas at an elevation of 3,317 feet (1,011 m), the highest low point of any U.S. state.
24. Jefferson County borders ten other counties, the most of any Colorado county.[a]
25. Delta County and the City and County of Denver each border only three other counties, the fewest of Colorado counties.[b]
26. The following twelve Colorado counties have a county seat with the same name as the county:
County County Seat
Alamosa County City of Alamosa
Boulder County City of Boulder
BroomfieldCity and County of Broomfield City and County of Broomfield
Conejos County unincorporated town of Conejos
Delta County City of Delta
DenverCity and County of Denver City and County of Denver
Eagle County Town of Eagle
Gunnison County City of Gunnison
Montrose County City of Montrose
Ouray County City of Ouray
Pueblo County City of Pueblo
Saguache County Town of Saguache
27. The name of each of the following two Colorado counties forms one part of the name of its county seat:
County County Seat
Cheyenne County Town of Cheyenne Wells
Morgan County City of Fort Morgan
28. Albeit somewhat confusing, the following towns have the same name as another county:
Town County
Arapahoe Cheyenne County
Dolores Montezuma County
Garfield Chaffee County
Jefferson Park County
Kiowa Elbert County
Kit Carson Cheyenne County
Las Animas Bent County
Moffat Saguache County
Montezuma Summit County
Pitkin Gunnison County
29. Weld County has the most incorporated municipalities of any Colorado county with 31.
30. The following nine Colorado counties have no incorporated municipalities other than their county seat:
County County Seat
Archuleta County Town of Pagosa Springs
Bent County City of Las Animas
BroomfieldCity and County of Broomfield City and County of Broomfield
DenverCity and County of Denver City and County of Denver
Hinsdale County Town of Lake City
Jackson County Town of Walden
Lake County City of Leadville
Mineral County Town of Creede
San Juan County Town of Silverton
31. Of all 64 Colorado counties, only Conejos County has a county seat that is not an incorporated municipality.
32. Only three Colorado county seats extend into other counties:
County County Seat Other Counties
Adams County City of Brighton Weld County
Arapahoe County City of Littleton Douglas County and Jefferson County
Gilpin County Central City Clear Creek County
33. The City and County of Denver and the City and County of Broomfield are the only two Colorado counties with enclaves.
34. The following 13 Colorado counties have highest mean elevation[c] of any county in the United States.
The 13 highest mean elevation counties in the United States

Rank[d] County Mean elevation[c] High point[15] Highest elevation[16][15][17] Low point[17] Lowest elevation[17] Elevation range[e]
1 Lake County 11,702.5 feet
3,567 m
Mount Elbert 14,440 feet
4,401 m
Arkansas River 8,965 feet
2,733 m
5,475 feet
1,669 m
2 Hinsdale County 11,300 feet
3,444 m
Uncompahgre Peak 14,315 feet
4,363 m
Lake Fork Gunnison River 8,285 feet
2,525 m
6,030 feet
1,838 m
3 Mineral County 11,116 feet
3,388 m
Phoenix Peak 13,902 feet
4,237 m
Rio Grande 8,330 feet
2,539 m
5,572 feet
1,698 m
4 San Juan County 11,085 feet
3,379 m
Vermilion Peak 13,900 feet
4,237 m
Animas River 8,270 feet
2,521 m
5,630 feet
1,716 m
5 Summit County 10,935.5 feet
3,333 m
Grays Peak 14,276 feet
4,351 m
Blue River 7,595 feet
2,315 m
6,681 feet
2,036 m
6 Alamosa County 10,928.5 feet
3,331 m
Blanca Peak 14,351 feet
4,374 m
Rio Grande 7,506 feet
2,288 m
6,845 feet
2,086 m
7 Saguache County 10,915 feet
3,327 m
Crestone Peak 14,300 feet
4,359 m
San Luis Creek 7,530 feet
2,295 m
6,770 feet
2,063 m
8 Costilla County 10,865.5 feet
3,312 m
Blanca Peak 14,351 feet
4,374 m
Rio Grande 7,380 feet
2,249 m
6,971 feet
2,125 m
9 Park County 10,705.5 feet
3,263 m
Mount Lincoln 14,293 feet
4,357 m
South Platte River 7,118 feet
2,170 m
7,175 feet
2,187 m
10 Chaffee County 10,661 feet
3,249 m
Mount Harvard 14,427 feet
4,397 m
Arkansas River 6,895 feet
2,102 m
7,532 feet
2,296 m
11 Clear Creek County 10,608 feet
3,233 m
Grays Peak 14,276 feet
4,351 m
Clear Creek 6,940 feet
2,115 m
7,336 feet
2,236 m
12 Rio Grande County 10,402 feet
3,171 m
Bennett Peak 13,209 feet
4,026 m
Rock Creek 7,595 feet
2,315 m
5,614 feet
1,711 m
13 Jackson County 10,353 feet
3,156 m
Clark Peak 12,956 feet
3,949 m
North Platte River 7,750 feet
2,362 m
5,206 feet
1,587 m

See also: List of highest mean elevation U.S. counties

See also

Notes

References

  1. ^ "Colorado County History". COGenWeb Project. April 29, 2011. Retrieved July 21, 2021.
  2. ^ Stanwyck, Don (2003). "Colorado County Evolution". COGenWeb Project. Archived from the original on February 5, 2007. Retrieved July 21, 2021.
  3. ^ City Council of the City and County of Denver v. Board of Commissioners of Adams County, 77 P. 858, 861 (1904).
  4. ^ "EPA County FIPS Code Listing". EPA.gov. Retrieved 2008-02-23.
  5. ^ a b National Association of Counties. "NACo - Find a county". Archived from the original on September 27, 2007. Retrieved 2008-04-30.
  6. ^ "Colorado County Seats". State of Colorado, Department of Public Health and Environment. 2007-01-30. Retrieved 2007-01-30.
  7. ^ a b c "Colorado Government History". State of Colorado, Department of Personnel & Administration, Colorado State Archives. 2001-04-18. Retrieved 2008-09-25.
  8. ^ "Census QuickFacts: Colorado". United States Census Bureau, Population Division. Retrieved March 31, 2022.
  9. ^ Merkl, Dameon (February 26, 2013), "What's in a Colorado name pronunciation?", The Denver Post, retrieved March 7, 2013
  10. ^ a b c "QuickFacts for Colorado". United States Census Bureau. Retrieved November 13, 2021.
  11. ^ a b c "Colorado Counties". Colorado Department of Local Affairs. 2021. Retrieved November 13, 2021.
  12. ^ a b c "State of Colorado Counties - Current/TAB20 - Data as of January 1, 2020". United States Census Bureau. January 1, 2020. Retrieved November 13, 2021.
  13. ^ "Colorado County High Points". peakbagger.com. Retrieved November 13, 2021.
  14. ^ a b Provisional Laws and Joint Resolutions of the General Assembly of Jefferson Territory. General Assembly of the Territory of Jefferson. 1859–1860. Retrieved 2011-05-05.
  15. ^ a b "Peak List". Peakbagger.com. Retrieved June 20, 2022.
  16. ^ "Elevation Point Query Service". United States Geological Survey. Retrieved June 20, 2022.
  17. ^ a b c "National Map Search". United States Geological Survey. Retrieved June 20, 2022.

Coordinates: 38°59′50″N 105°32′52″W / 38.9972°N 105.5478°W / 38.9972; -105.5478 (State of Colorado)