List of counties in Colorado

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

Adams

Alam

Arapahoe

Arch

Baca

Bent

Boul

Bro

Chaf

Cheyenne

Cle

Conejos

Cost

Crow

Cust

Delta

Den

Dolores

Doug

Eagle

Elbert

El Paso

Fremont

Garfield

Gil

Grand

Gunnison

Hins

Huerfano

Jacks

Jef

Kiowa

Kit
Carson

Lake

La
Plata

Larimer

Las Animas

Lincoln

Logan

Mesa

Min

Moffat

Montez

Montrose

Morg

Otero

Our

Park

Phil

Pitkin

Prow

Pueblo

Rio Blanco

Rio G

Routt

Saguache

SJ

San Miguel

Sedg

Sum

Tell

Wash

Weld

Yuma

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.	519,572	1,182.29 sq mi (3,062 km2)
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.	16,376	723.21 sq mi (1,873 km2)
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.	655,070	804.41 sq mi (2,083 km2)
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.	13,359	1,354.53 sq mi (3,508 km2)
Baca County	009	Springfield	1889-04-16	Split from Las Animas County.	Named in honor of pioneer and Colorado territorial legislator Felipe Baca.	3,506	2,558.48 sq mi (6,626 km2)
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.	5,650	1,541.07 sq mi (3,991 km2)
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.	330,758	740.48 sq mi (1,918 km2)
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.	74,112	33.57 sq mi (87 km2)
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.	19,476	1,014.12 sq mi (2,627 km2)
Cheyenne County	017	Cheyenne Wells	1889-03-25	Split from Elbert and Bent counties.	Named for the Cheyenne Nation of Native Americans.	1,748	1,781.90 sq mi (4,615 km2)
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.	9,397	396.53 sq mi (1,027 km2)
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.	7,461	1,290.22 sq mi (3,342 km2)
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.	3,499	1,229.38 sq mi (3,184 km2)
Crowley County	025	Ordway	1911-05-29	Split from Otero County.	Named in honor of Colorado State Senator John H. Crowley.	5,922	800.27 sq mi (2,073 km2)
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.	4,704	739.24 sq mi (1,915 km2)
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.	31,196	1,149.44 sq mi (2,977 km2)
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.	715,522	155.66 sq mi (403 km2)
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.	2,326	1,076.93 sq mi (2,789 km2)
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.	357,978	842.30 sq mi (2,182 km2)
Eagle County	037	Eagle	1883-02-11	Split from Summit County.	Named for the Eagle River which originates in the county.	55,731	1,700.76 sq mi (4,405 km2)
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.	730,395	2,128.60 sq mi (5,513 km2)
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.	26,062	1,849.08 sq mi (4,789 km2)
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.	48,939	1,533.09 sq mi (3,971 km2)
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.	61,685	2,958.23 sq mi (7,662 km2)
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.	5,808	150.15 sq mi (389 km2)
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.	15,717	1,868.53 sq mi (4,839 km2)
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.	16,918	3,259.22 sq mi (8,441 km2)
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.	788	1,123.35 sq mi (2,909 km2)
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.	6,820	1,592.37 sq mi (4,124 km2)
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.	1,379	1,619.75 sq mi (4,195 km2)
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.	582,910	772.85 sq mi (2,002 km2)
Kiowa County	061	Eads	1889-04-11	Split from Bent County.	Named for the Kiowa Nation of Native Americans.	1,446	1,785.90 sq mi (4,625 km2)
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.	7,087	2,162.43 sq mi (5,601 km2)
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.	55,638	1,700.44 sq mi (4,404 km2)
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.	7,436	383.55 sq mi (993 km2)
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.	359,066	2,631.75 sq mi (6,816 km2)
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.	14,555	4,773.27 sq mi (12,363 km2)
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.	5,675	2,585.21 sq mi (6,696 km2)
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.	21,528	1,845.31 sq mi (4,779 km2)
Mesa County	077	Grand Junction	1883-02-14	Split from Gunnison County.	Named for the mesa formations which are widespread through the area.	155,703	3,345.69 sq mi (8,665 km2)
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.	865	878.16 sq mi (2,274 km2)
Moffat County	081	Craig	1911-02-27	Split from Routt County.	Named in honor of railroad pioneer David H. Moffat.	13,292	4,755.86 sq mi (12,318 km2)
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.	25,849	2,035.80 sq mi (5,273 km2)
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.	42,679	2,246.43 sq mi (5,818 km2)
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 .	29,111	1,293.83 sq mi (3,351 km2)
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.	18,690	1,267.66 sq mi (3,283 km2)
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.	4,874	542.30 sq mi (1,405 km2)
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.	17,390	2,209.36 sq mi (5,722 km2)
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.	4,530	688.30 sq mi (1,783 km2)
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.	17,358	970.37 sq mi (2,513 km2)
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.	11,999	1,645.37 sq mi (4,261 km2)
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.	168,162	2,396.77 sq mi (6,208 km2)
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.	6,529	3,226.24 sq mi (8,356 km2)
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.	11,539	913.10 sq mi (2,365 km2)
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.	24,829	2,362.11 sq mi (6,118 km2)
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]	6,368	3,168.32 sq mi (8,206 km2)
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.	705	388.99 sq mi (1,007 km2)
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.	8,072	1,290.76 sq mi (3,343 km2)
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).	2,404	548.83 sq mi (1,421 km2)
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.	31,055	618.92 sq mi (1,603 km2)
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.	24,710	558.58 sq mi (1,447 km2)
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.	4,817	2,522.90 sq mi (6,534 km2)
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.	328,981	4,013.84 sq mi (10,396 km2)
Yuma County	125	Wray	1889-03-15	Split from Washington County.	Named for the Quechan (Yuma) Nation of Native Americans.	9,988	2,369.61 sq mi (6,137 km2)

Table of county data[]

An enlargeable map of the 64 counties of the state of Colorado

The following sortable table lists the 64 counties of the state of Colorado with the following information:

1. The official name of the county,^[10]
2. The county seat,^[11]
3. The date the county was established,^[12]
4. A link to a detailed transportation map of the county.^[13]
5. The population rank among the 64 counties of Colorado as of April 1, 2020
6. The county population as of April 1, 2020, as enumerated by the 2020 United States Census
7. The percent population change from April 1, 2010 to April 1, 2020
8. The county population as of April 1, 2010, as enumerated by the 2010 United States Census
9. The percent population change from April 1, 2000 to April 1, 2010
10. The county population as of April 1, 2000, as enumerated by the 2000 United States Census
11. The average population density per land area of the county as of April 1, 2020
12. The land area of the county as of January 1, 2020, as determined by the United States Census Bureau^[14]
13. The water area of the county as of January 1, 2020, as determined by the United States Census Bureau^[14]
14. The total area of the county as of January 1, 2020, as determined by the United States Census Bureau^[14]
15. The minimum surface elevation in the county,^[15][c][d]
16. The maximum surface elevation in the county,^[16][c][e]
17. The centroid coordinates of the county as of January 1, 2020, as determined by the United States Census Bureau^[14]

The 64 Counties of the State of Colorado

County Name	County Seat	Date Established	Map	Population							Area			Elevation		Coordinates
				2020 Rank	2020 Census	Change	2010 Census	Change	2000 Census	2020 Density	Land	Water	Total	Min	Max
Adams County	Brighton	1902-11-15	map	5	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)
Alamosa County	Alamosa	1913-03-08	map	31	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)
Arapahoe County	Littleton	1861-11-01	map	3	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)
Archuleta County	Pagosa Springs	1885-04-14	map	34	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)
Baca County	Springfield	1889-04-16	map	55	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)
Bent County	Las Animas	1870-02-11	map	50	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)
Boulder County	Boulder	1861-11-01	map	8	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)
City and County of Broomfield	Broomfield	2001-11-15	map	12	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)
Chaffee County	Salida	1879-02-10	map	26	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)
Cheyenne County	Cheyenne Wells	1889-03-25	map	59	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)
Clear Creek County	Georgetown	1861-11-01	map	39	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)
Conejos County	Conejos	1861-11-07	map	41	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)
Costilla County	San Luis	1861-11-01	map	56	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)
Crowley County	Ordway	1911-05-29	map	47	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)
Custer County	Westcliffe	1877-03-09	map	53	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)
Delta County	Delta	1883-02-11	map	18	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)
City and County of Denver	Denver	1902-12-01	map	2	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)
Dolores County	Dove Creek	1881-03-04	map	58	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)
Douglas County	Castle Rock	1861-11-01	map	7	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)
Eagle County	Eagle	1883-02-11	map	14	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)
El Paso County	Colorado Springs	1861-11-01	map	1	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)
Elbert County	Kiowa	1874-02-02	map	21	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)
Fremont County	Cañon City	1861-11-01	map	16	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)
Garfield County	Glenwood Springs	1883-02-10	map	13	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)
Gilpin County	Central City	1861-11-01	map	48	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)
Grand County	Hot Sulphur Springs	1874-02-02	map	32	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)
Gunnison County	Gunnison	1877-03-09	map	30	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)
Hinsdale County	Lake City	1874-02-10	map	63	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)
Huerfano County	Walsenburg	1861-11-01	map	44	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)
Jackson County	Walden	1909-05-05	map	61	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)
Jefferson County	Golden	1861-11-01	map	4	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)
Kiowa County	Eads	1889-04-11	map	60	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)
Kit Carson County	Burlington	1889-04-11	map	43	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)
La Plata County	Durango	1874-02-10	map	15	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)
Lake County	Leadville	1861-11-01	map	42	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)
Larimer County	Fort Collins	1861-11-01	map	6	359,066	+19.84%	299,630	+19.14%	251,489	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)
Las Animas County	Trinidad	1866-02-09	map	33	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)
Lincoln County	Hugo	1889-04-11	map	49	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)
Logan County	Sterling	1887-02-25	map	25	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)
Mesa County	Grand Junction	1883-02-14	map	11	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)
Mineral County	Creede	1893-03-27	map	62	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)
Moffat County	Craig	1911-02-27	map	35	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)
Montezuma County	Cortez	1889-04-16	map	22	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)
Montrose County	Montrose	1883-02-11	map	17	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)
Morgan County	Fort Morgan	1889-02-19	map	20	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)
Otero County	La Junta	1889-03-25	map	27	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)
Ouray County	Ouray	1877-01-18	map	51	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)
Park County	Fairplay	1861-11-01	map	28	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)
Phillips County	Holyoke	1889-03-27	map	54	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)
Pitkin County	Aspen	1881-02-23	map	29	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)
Prowers County	Lamar	1889-04-11	map	36	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)
Pueblo County	Pueblo	1861-11-01	map	10	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)
Rio Blanco County	Meeker	1889-03-25	map	45	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)
Rio Grande County	Del Norte	1874-02-10	map	37	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)
Routt County	Steamboat Springs	1877-01-29	map	23	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)
Saguache County[b][9]	Saguache	1866-12-29	map	46	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)
San Juan County	Silverton	1876-01-31	map	64	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)
San Miguel County	Telluride	1883-03-02	map	40	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)
Sedgwick County	Julesburg	1889-04-09	map	57	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)
Summit County	Breckenridge	1861-11-01	map	19	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)
Teller County	Cripple Creek	1899-03-23	map	24	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)
Washington County	Akron	1887-02-09	map	52	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)
Weld County	Greeley	1861-11-01	map	9	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)
Yuma County	Wray	1889-03-15	map	38	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 of Colorado	Denver	1876-08-01	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)

County high points[]

Former counties[]

The sortable table below 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^[17] 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. The table includes the following information:

1. The official name of the county,
2. The territory or state,
3. The date the county was created,
4. The date the county was abolished or excluded from the new Territory of Colorado, and
5. Historical notes.

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:^[17]

5. On November 1, 1861, the Territory of Colorado created the 17 original Colorado counties:^[12]

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.^[f]

25. Delta County and the City and County of Denver each border only three other counties, the fewest of Colorado counties.^[g]

26. The following twelve Colorado counties have a county seat with the same name as the county:

27. The name of each of the following two Colorado counties forms one part of the name of its county seat:

28. Albeit somewhat confusing, the following towns have the same name as another 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:

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:

33. The City and County of Denver and the City and County of Broomfield are the only two Colorado counties with enclaves.

34. Arapahoe County, Boulder County, and Jefferson County are the only three dismembered Colorado counties with exclaves.

34. San Juan County has the highest mean elevation of any U.S. county at 11,240 feet (3,426 m). The 25 highest U.S. counties by mean elevation are:^[18]

Highest Counties in the United States

Rank	County	State	Mean Elevation
1	San Juan County	Colorado	11,240 feet (3,426 m)
2	Hinsdale County	Colorado	10,826 feet (3,300 m)
3	Lake County	Colorado	10,790 feet (3,289 m)
4	Mineral County	Colorado	10,411 feet (3,173 m)
5	Summit County	Colorado	10,365 feet (3,159 m)
6	Clear Creek County	Colorado	10,264 feet (3,128 m)
7	Pitkin County	Colorado	9,940 feet (3,030 m)
8	Chaffee County	Colorado	9,915 feet (3,022 m)
9	Park County	Colorado	9,572 feet (2,918 m)
10	Gunnison County	Colorado	9,488 feet (2,892 m)
11	Gilpin County	Colorado	9,236 feet (2,815 m)
12	Grand County	Colorado	9,204 feet (2,805 m)
13	Saguache County	Colorado	9,193 feet (2,802 m)
14	Teller County	Colorado	9,052 feet (2,759 m)
15	Rio Grande County	Colorado	9,011 feet (2,747 m)
16	Custer County	Colorado	8,988 feet (2,740 m)
17	Eagle County	Colorado	8,987 feet (2,739 m)
18	Ouray County	Colorado	8,951 feet (2,728 m)
19	Jackson County	Colorado	8,863 feet (2,701 m)
20	Conejos County	Colorado	8,774 feet (2,674 m)
21	Costilla County	Colorado	8,681 feet (2,646 m)
22	Taos County	New Mexico	8,510 feet (2,594 m)
23	Summit County	Utah	8,388 feet (2,557 m)
24	Dolores County	Colorado	8,280 feet (2,524 m)
25	Archuleta County	Colorado	8,101 feet (2,469 m)

See also[]

• Colorado
  • Bibliography of Colorado
  • Index of Colorado-related articles
  • Outline of Colorado
• Colorado statistical areas
• Geography of Colorado
• History of Colorado
• List of places in Colorado
  • List of mountain passes in Colorado
  • List of mountain peaks of Colorado
  • List of mountain ranges of Colorado
  • List of populated places in Colorado
    • List of census-designated places in Colorado
    • List of county seats in Colorado
    • List of forts in Colorado
    • List of ghost towns in Colorado
    • List of historic places in Colorado
    • List of municipalities in Colorado
    • List of populated places in Colorado by county
    • List of post offices in Colorado
  • List of rivers of Colorado
• List of protected areas of Colorado

Notes[]

References[]

External links[]

• Colorado state government website
• Colorado tourism website
• History Colorado website

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