County · code 08035
Douglas CountyColorado
Douglas County is a county in Colorado with its seat in Castle Rock. It was established in 1861 and named after Stephen A. Douglas.
- Founded1861
- County seatCastle Rock
- Named forStephen A. Douglas
- Land area840 sq mi + 2.6 sq mi water
- Population357,978 2020 Census
- Parcels mapped165,672 checked 13 October 2026
Where it is
Douglas on the map of Colorado
Colorado has 64 counties and county equivalents, each with its own records office. Shapes with a page are links.
History
Founded in 1861
An old deed may name a county that no longer exists, or a boundary that has since moved.
Douglas County was created in 1861 by Colorado Territory from non-county area. In 1865, it was attached to Arapahoe County for judicial purposes, then fully organized and detached in 1867. In 1874, Douglas County lost territory to the creation of Elbert County.
- 1861Douglas County created Douglas created by Colorado Territory from non-county area. · Colo. Terr. Laws 1861, 1st sess., sec. 14/p. 54
- 1865Changed Douglas attached to Arapahoe "for judicial purposes." · Colo. Terr. Laws 1865, 4th sess., sec. 15/p. 53
- 1867Changed Douglas fully organized, detached from Arapahoe. · Colo. Terr. Laws 1866, 6th sess., pp. 60-61
- 1874Lost territory Douglas lost to creation of Elbert. · Colo. Terr. Laws 1874, 10th sess., pp. 69-70
Land and parcels
What the maps cover in Douglas
Who publishes each layer, how good it is, and when we last checked.
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Parcels Good enough
Lot lines and tax-map numbers for 165,672 parcels. Drawn for tax purposes: usually within a few feet of a survey, but not a survey.
edited 13 October 2026 · checked 13 October 2026 -
Address points Missing
No public address points layer found for Douglas County yet.
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Buildings Reference
Roof outlines traced from aerial imagery from FEMA Response Geospatial Office with Oak Ridge National Laboratory (ORNL). Good for seeing what is on a lot; not accurate enough to set a fence from.
checked 18 October 2026
- Official
- from the office that keeps the record
- Good enough
- a reliable statewide or national copy
- Fallback
- a guide only; check the official record
- Missing
- nothing public found yet
People and land
Douglas by the Census
Source: US Census Bureau, 2020 Census; US Census Bureau, 2020 Gazetteer Files. Not endorsed or certified by the Census Bureau.
Rules and offices
Who to ask before you build, dig or sell
Official county pages only. We link to them; we do not copy them, because they change.
Inside a city or town, permits usually come from that city rather than the county.
Permits
County government
- County government
The official website of Douglas County.
See your own lot on these maps
Open Douglas County on Parcel Chart's free map and click your parcel. Save it with a free account; the full record of your place (site map, projects, documents) is Pro, in early access.
Questions
Common questions about Douglas County
- When was Douglas County founded?
- Douglas County was founded in 1861, and named after Stephen A. Douglas.
- What is the county seat of Douglas County?
- The county seat of Douglas County is Castle Rock.
- Is there an online parcel map for Douglas County?
- Yes. A public source publishes a parcel map of 165,672 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.
- Has Douglas County's boundary or name changed?
- Douglas County was created in 1861. Since then the Atlas of Historical County Boundaries records 3 later changes, chiefly involving Arapahoe County and Elbert County.
- Who issues building permits in Douglas County?
- The county's page on building permits: Permits (Building). Inside a city or town, ask that city first.
- Is my lot in a flood zone?
- We do not have flood maps for Douglas County yet. Look up the address on FEMA's Flood Map Service Center, which shows the effective flood map for any lot.
Nearby