List of 64 counties in the U.S. state of Colorado:
  1. Adams County
  2. Alamosa County
  3. Arapahoe County
  4. Archuleta County
  5. Baca County
  6. Bent County
  7. Boulder County
  8. Broomfield County
  9. Chaffee County
  10. Cheyenne County
  11. Clear Creek County
  12. Conejos County
  13. Costilla County
  14. Crowley County
  15. Custer County
  16. Delta County
  17. Denver County
  18. Dolores County
  19. Douglas County
  20. Eagle County
  21. El Paso County
  22. Elbert County
  23. Fremont County
  24. Garfield County
  25. Gilpin County
  26. Grand County
  27. Gunnison County
  28. Hinsdale County
  29. Huerfano County
  30. Jackson County
  31. Jefferson County
  32. Kiowa County
  33. Kit Carson County
  34. La Plata County
  35. Lake County
  36. Larimer County
  37. Las Animas County
  38. Lincoln County
  39. Logan County
  40. Mesa County
  41. Mineral County
  42. Moffat County
  43. Montezuma County
  44. Montrose County
  45. Morgan County
  46. Otero County
  47. Ouray County
  48. Park County
  49. Phillips County
  50. Pitkin County
  51. Prowers County
  52. Pueblo County
  53. Rio Blanco County
  54. Rio Grande County
  55. Routt County
  56. Saguache County
  57. San Juan County
  58. San Miguel County
  59. Sedgwick County
  60. Summit County
  61. Teller County
  62. Washington County
  63. Weld County
  64. Yuma County