Colorado counties

The U.S state of Colorado is divided into 64 counties. Counties are important units of government in Colorado since the state has no secondary civil subdivisions, such as townships. Two of these counties, the City and County of Denver and the City and County of Broomfield, have consolidated city and county governments.

Table
The following sortable table lists the 64 counties of the state of Colorado with the following information:
 * 1) The official name of the county,
 * 2) The date the county was established,
 * 3) The county seat,
 * 4) The rank among the 64 counties of Colorado by population as of April 1, 2010, as counted by the 2010 United States Census,
 * 5) The county population as of April 1, 2010, as counted by the 2010 United States Census,
 * 6) The county population as of April 1, 2000, as counted by the 2000 United States Census,
 * 7) The percent population change from April 1, 2000, to April 1, 2010,
 * 8) A link to a detailed transportation map of the county.
 * 9) The average population density of the county,
 * 10) The land area of the county,
 * 11) The water area of the county,
 * 12) The total area of the county,
 * 13) The maximum surface elevation in the county,
 * 14) The minimum surface elevation in the county,
 * 15) The reference latitude of the county, and
 * 16) The reference longitude of the county.

Historic 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 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. Larimer County is the home of the most ancient known archaeological site in the Rocky Mountain region. Artifacts more than 13,000 years old have been found at the Lindenmeier Site.
 * 2. Costilla County was the first area within the present State of Colorado to be settled by Europeans in 1851.
 * 3. 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.
 * 4. 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.
 * 5. On November 28, 1859, the extralegal Territory of Jefferson created 12 counties:


 * 6. On November 1, 1861, the Territory of Colorado created the 17 original Colorado counties:


 * 7. 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.
 * 8. Guadalupe County was the first Colorado county to be renamed in 1861.
 * 9. Las Animas County was the first new Colorado county to be created (in 1866) after the original 17 counties.
 * 10. Greenwood County was the longest lived former Colorado county, existing four years from 1870 to 1874.
 * 11. Carbonate County was the shortest lived former Colorado county, existing only two days in 1879 before being dissolved.
 * 12. The City and County of Broomfield became the newest Colorado county in 2001.
 * 13. Las Animas County is the most extensive Colorado county.
 * 14. The City and County of Broomfield is the least extensive Colorado county.
 * 15. The El Paso County is the most populous Colorado county.
 * 16. San Juan County is the least populous Colorado county.
 * 17. The El Paso County, City and County of Denver, Arapahoe County, and Jefferson County each have a population in excess of 500,000.
 * 18. San Juan County, Mineral County, and Hinsdale County each have a population of less than 1000.
 * 19. The City and County of Denver is the most densely populated Colorado county.
 * 20. Hinsdale County is the least densely populated Colorado county.
 * 21. Hinsdale County, Kiowa County, Mineral County, and Jackson County have fewer than one resident per square mile (0.386 km−2).
 * 22. Lake County has the highest point in Colorado at the summit of Mount Elbert at 14440 ft elevation (the highest point in the entire Rocky Mountains).
 * 23. Yuma County has the lowest point in Colorado where the Arikaree River flows into Kansas at 3317 ft elevation (the highest low point of any U.S. state).
 * 24. Jefferson County borders ten other counties, the most of any Colorado county.
 * 25. Delta County and the City and County of Denver each border only three other counties, the fewest of Colorado counties.
 * 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. Weld County has the most incorporated municipalities of any Colorado county with 31.
 * 29. The following nine Colorado counties have no incorporated municipalities other than the county seat:


 * 30. Of all 64 Colorado counties, only Conejos County has a county seat that is not an incorporated municipality.
 * 31. Only three Colorado county seats extend into other counties:


 * 32. The City and County of Denver and the City and County of Broomfield are the only two Colorado counties with enclaves.
 * 33. 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 11240 ft. The 25 highest U.S. counties by mean elevation are: