| | Adams County | CO | 08001 | | Denver-Aurora-Centennial,
CO 19740 | Denver-Aurora-Greeley, CO 216 | Central | in metro of > 1m | nonspecialized | https://maps.google.com/?q=AdamsCounty+CO |
| | Alamosa County | CO | 08003 | | Alamosa, CO 10480 | | Central | not in metro; pop > 5K
< 20k;
non-metro-adjacent | federal/state
government-dependent | https://maps.google.com/?q=AlamosaCounty+CO |
| | Arapahoe County | CO | 08005 | | Denver-Aurora-Centennial,
CO 19740 | Denver-Aurora-Greeley, CO 216 | Central | in metro of > 1m | nonspecialized | https://maps.google.com/?q=ArapahoeCounty+CO |
| | Archuleta County | CO | 08007 | | | | | not in metro; pop > 5K
< 20k;
non-metro-adjacent | recreation | https://maps.google.com/?q=ArchuletaCounty+CO |
| | Baca County | CO | 08009 | | | | | not in metro; pop <
5k; non-metro-adjacent | farm-dependent | https://maps.google.com/?q=BacaCounty+CO |
| | Bent County | CO | 08011 | | | | | not in metro; pop <
5k; non-metro-adjacent | farm-dependent | https://maps.google.com/?q=BentCounty+CO |
| | Boulder County | CO | 08013 | | Boulder, CO 14500 | Denver-Aurora-Greeley, CO 216 | Central | in metro of > 250k
< 1m | nonspecialized | https://maps.google.com/?q=BoulderCounty+CO |
| | Broomfield County | CO | 08014 | | Denver-Aurora-Centennial,
CO 19740 | Denver-Aurora-Greeley, CO 216 | Central | in metro of > 1m | nonspecialized | https://maps.google.com/?q=BroomfieldCounty+CO |
| | Chaffee County | CO | 08015 | | | | | not in metro; pop > 5k
< 20k; metro-adjacent | recreation | https://maps.google.com/?q=ChaffeeCounty+CO |
| | Cheyenne County | CO | 08017 | | | | | not in metro; pop <
5k; non-metro-adjacent | farm-dependent | https://maps.google.com/?q=CheyenneCounty+CO |