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Adams County, Colorado
Alamosa County, Colorado
Arapahoe County, Colorado
Arapahoe County, Kansas Territory
Archuleta County, Colorado
Baca County, Colorado
Bent County, Colorado
Boulder County, Colorado
Chaffee County, Colorado
Cheyenne County, Colorado
Clear Creek County, Colorado
Conejos County, Colorado
Costilla County, Colorado
Crowley County, Colorado
Custer County, Colorado
Delta County, Colorado
Dolores County, Colorado
Douglas County, Colorado
Eagle County, Colorado
El Paso County, Colorado
Fremont County, Colorado
Garfield County, Colorado
Gilpin County, Colorado
Grand County, Colorado
Grand Lake (Colorado)
Gunnison County, Colorado
Hinsdale County, Colorado
Huerfano County, Colorado
Jackson County, Colorado
Jefferson County, Colorado
Arrappahoe County, Jefferson TerritoryBroderick County, Kansas TerritoryBroomfield,_ColoradoEl Paso County, Jefferson TerritoryEl Paso County, Kansas TerritoryFountain County, Jefferson TerritoryFremont County, Kansas TerritoryHeele County, Jefferson TerritoryJackson County, Jefferson TerritoryJefferson County, Jefferson Territory