Highlands Ranch is an unincorporated community and a census-designated place (CDP) located in and governed by Douglas County, Colorado, United States. The CDP is a part of the Denver–Aurora–Lakewood, CO Metropolitan Statistical Area. The population of the Highlands Ranch CDP was 96,713 at the United States Census 2010, making it the most populous unincorporated community in the State of Colorado. The Highlands Ranch Metropolitan District provides services to the community, which lies in ZIP Codes 80126, 80129, 80130, and 80163 (for post office boxes).
Like many parts of the Colorado Front Range, the first residents of the area were Native Americans. The area was populated by a number of nomadic tribes, including the Ute, Cheyenne and Arapaho tribes. Because it was part of the Mississippi River Drainage Area, it was claimed by France by French explorer René-Robert Cavelier, Sieur de La Salle and it was named as part of "Louisiana" in 1682. The Spanish gained Louisiana in 1763, and returned it to France in 1801. This area of what is now Northern Douglas County, was in the Louisiana Purchase when it was sold to the United States in 1803.
The Stephen Harriman Long Expedition of 1820 entered the area at the beginning of July 1820. That was the first documented exploration of the area by European or United States explorers.
Much of the Denver Metro Area began to be settled as ranch land starting in 1859, but because of a lack of water in the area, it was not permanently settled until around 1870.