Douglas County covers 843 square miles between Denver and Colorado Springs on the western Great Plains along the Front Range. The county was established in 1861 as one of the original seventeen counties of the Colorado Territory. It is bordered to the north by Arapahoe County, to the east by Elbert County, to the south by El Paso and Teller Counties, and to the west by Jefferson County. The county took its name from Stephen A. Douglas, a popular politician in the 1850s who argued for popular sovereignty and who ran against Abraham Lincoln in the 1858 senate race and in the 1860 presidential race.

With a population of 322,387, Douglas County is the seventh-most populous county in the state. The county seat is Castle Rock, a burgeoning community just south of the Denver Metro area linked to the capital by Interstate 25. Other towns include the Denver suburbs of Highlands Ranch, Lone Tree, and Parker, and Larkspur, located south of Castle Rock on I-25.

Douglas County sits atop the western edge of the Palmer Divide. The broad ridge, which runs from the Rocky Mountains in the west to the town of Limon in the east, divides tributaries of the South Platte and Arkansas Rivers and ranges between 6,000 and 7,500 feet in elevation. Because of this, the county’s climate is generally wetter than those to the north and south. The county also includes part of the Pike National Forest, Roxborough State Park, Castlewood Canyon State Park, and the Chatfield State Recreation Area. The South Platte River forms the county’s northwestern border with Jefferson County, flowing out of the foothills into Chatfield Lake. Plum Creek, a tributary of the Platte, begins in the foothills southwest of Larkspur and runs through Castle Rock and the small community of Sedalia before it also empties into Chatfield Lake.

Native Americans

Douglas County’s archaeological record holds evidence of human occupation from about 13,000 years ago. Projectile points, millstones, and other early tools found at the Lamb Spring site and others indicate the presence of people from the Clovis, Folsom, and Plano periods. These early people were hunter-gatherers, following the seasonal migrations of large game, collecting dietary plants, and camping near the foothills along waterways during the winter. The earliest Paleo-Indians hunted large game, including mammoth and camels. Later groups hunted more familiar large game such as elk, bison, and deer.

Modern Native American groups were also hunter-gatherers. Ute people occupied the mountains of western Douglas County by the sixteenth century, following the same seasonal migration routes as earlier indigenous groups. After tracking game into the high country during the summer and fall, Utes moved to the base of the mountains and set up winter camps in the areas of present-day Denver and Castle Rock. Utes lived in temporary or mobile dwellings such as wickiups and tipis.

By the early nineteenth century, the Cheyenne and Arapaho had migrated to the Douglas County area. These two groups moved southwest from the upper Midwest, where they had historically lived in more sedentary farming communities. During their westward migration the Cheyenne and Arapaho adopted a nomadic way of life centered around the horse, which they used to follow the great buffalo herds across the plains. While both groups primarily lived on the plains, their pursuit of buffalo and other game often led them into the mountains, where they fought with the Ute for access to hunting grounds. Like the Ute, the Cheyenne and Arapaho often wintered along water sources such as Plum Creek and the South Platte, using trees and plants in the area for shelter and fuel.

Early American Era

The United States acquired the area of Douglas County as part of the Louisiana Purchase in 1803, but the area was nonetheless controlled by Ute, Cheyenne, and Arapaho for the next several decades. Fur trappers arrived during the 1820s to trap beaver, and during the 1830s the area’s native groups harvested buffalo hides to trade at Bent’s Fort farther south. In the Treaty of Fort Laramie (1851), the Cheyenne and Arapaho agreed to allow safe westward passage of white travelers as long as they retained sovereignty over their land in Colorado.

However, events later in the decade refocused the US government’s attention on Colorado. In 1858 the William Green Russell Party, a group of prospectors from Georgia, followed the Cherokee Trail, a popular route west that ran through Douglas County, to prospect for gold in the Rockies. They reportedly found some flakes of gold in Russellville Gulch, east of modern Castle Rock, but the party soon moved on toward present-day Denver, where they found an even larger deposit. News of their findings in present Douglas County and Denver set off the Colorado Gold Rush (1858–59).

The Cherokee Trail—also called the Trapper’s Trail—and the Smoky Hill Trail had been used by Cherokees and prospectors to participate in both the California and Colorado gold rushes in the mid-nineteenth century. As part of this trail, two stage stops in present Douglas County, Seventeen Mile House and Twenty Mile House, functioned as rest stops for travelers. Their names reflected the distance from Denver.

County Development

The Colorado Territory was established in 1861, and Douglas County became one of the original seventeen counties. It was named for Stephen A. Douglas, a popular politician who debated Abraham Lincoln before the Civil War. The county originally stretched from the Rocky Mountains to the Kansas border. The first county seat was Franktown, a ranching and farming community along the Jimmy Camp Trail, another popular route for early miners and travelers. After Colorado became a state in 1876, the county shrunk to its current size following the creation of Elbert, Lincoln, and Kit Carson Counties.

The Treaty of Fort Wise in 1861 led to the removal of the Cheyenne and Arapaho to a reservation in eastern Colorado, and in 1864 the US government approved a treaty with the Ute Indians that granted the United States the entire Front Range. However, all three groups continued to visit Douglas County to hunt and trade with white immigrants, who arrived to take advantage of the Homestead Act of 1862.

The relatively high rainfall of the Palmer Divide supports more trees and vegetation than surrounding areas, making the land around Plum Creek, the South Platte, and Cherry Creek ideal for the development of farming and cattle ranching. Sawmills converted felled trees into lumber for local ranches and farmhouses, as well as for buildings in developing Denver. Additionally, rhyolite quarries near present Castle Rock provided stone for buildings in Douglas County, Auraria, and Denver.

Quarry workers and ranchers in the Plum Creek valley established the town of Castle Rock in the 1870s. William Jackson Palmer’s Denver & Rio Grande Railroad (D&RG) reached Castle Rock in the early 1870s and built a train depot in the town, which then became the county seat in 1874. The railroad lowered the costs of shipping local timber, rhyolite, and cheese, and Castle Rock became an important stop along a Front Range rail corridor that eventually extended south to Colorado Springs and Pueblo.

One of the earliest farmers in the area was Dad Rufus Clark, who set up a successful potato farm near present-day Highlands Ranch. Dairies, creameries, and cheese factories also developed in the county, including the Big Dry Creek Cheese Ranch, which was set up in the 1870s.

Drawn by financial interests in timber, mining, ranching, farming, and real estate, the eastern industrialist Samuel A. Long filed for a homestead in Douglas County in 1884. Four years later he had acquired 2,000 additional acres, and in 1891 Long built a modest farmhouse on the property. In 1891 Long sold the house to rancher John Springer, who expanded it into the Highlands Ranch Mansion. Long went on to become one of Douglas County’s pioneers of dryland farming—farming with low-water crops such as winter wheat—in the late 1890s. Springer, meanwhile, kept buying ranch land in the surrounding area, eventually owning 12,000 acres on which he raised horses and cattle.

The Englishman Charles Allis also arrived during the 1880s and set up a ranch near Castle Rock. The Allis ranch eventually became known as Greenland and raised cattle, pigs, milk cows, and sheep on more than 1,700 acres. The ranch stayed in the family for generations, and its proprietors became leading citizens in Douglas County; Charles’s son Alfred not only helped usher the ranch through the Great Depression but also served on the Greenland School Board and as a firefighter with the Larkspur Fire Department. He also served as postmaster of Larkspur in the 1970s.

The Douglas County courthouse was completed in 1890 with stone from local rhyolite quarries. That same year, Denver officials commissioned the building of Castlewood Dam to ensure proper irrigation for local farms and ranches.

In the early 1880s a second rail line was completed through the county. The Denver & New Orleans (D&NO) connected Denver and Pueblo, with a stop in the area of present-day Parker. Parker began as a collection of homesteads around Twenty Mile House, and the railroad allowed the town to expand. By the turn of the century it included a saloon, mercantile, dry goods store, water tower and pump house, creamery, and school.

Twentieth Century

In 1906 a new industry came to Douglas County—DuPont’s dynamite factory. DuPont bought the site of present-day  Louviers in 1906, where it built the town and the factory. Initially, workers lived in tents, but the company soon built homes for the workers, the first of which were completed in 1908. By 1917 the company had built a clubhouse as a community center for workers in the town. The company town flourished until the factory closed in the 1970s.

Pike National Forest, covering the western part of Douglas County, was also established in 1906. In 1912 the Forest Service built a fire lookout in the foothills called the Devil’s Head Lookout, which is still used today.

Disaster hit the county in 1933 when Castlewood Dam broke following several days of heavy rain. A torrent of water gushed down Cherry Creek toward Parker and Denver, killing two people and causing extensive property damage.

During the first half of the twentieth century, ranches and creameries continued operation, and Douglas County towns remained relatively small and rural. In 1940 about 67 percent of the land in Douglas County was covered by farms.

From Ranches to Subdivisions

The 1960s brought the first urban sprawl from the Denver area. The population of Colorado grew substantially after World War II. As Denver and its suburbs grew, so did the need for housing and transportation. Construction of Interstate 25 between Castle Rock and Denver was completed in 1963, giving Douglas County a connection to both Denver and Colorado Springs along the state’s newest and longest north-south highway.

Motorists had only been using the new highway for two years when the largest flood in Douglas County history occurred in June 1965. Following several days of rain, a tornado hit Palmer Lake. With the ground saturated, a flood began and surged along East Plum Creek into Castle Rock. In addition to inundating the city, the floodwaters washed out I-25 and all the bridges between Castle Rock and Denver. The torrent destroyed buildings in Louviers, and as the floodwaters reached Denver, the city closed roads and evacuated buildings.

Despite the setback from the flood, development continued in Douglas County over the next several decades. New neighborhoods were built in the Parker area in the 1960s, and in 1979 Mission Viejo bought the Highlands Ranch area. The developer finished building the modern residential community of Highlands Ranch in 1981. The city of Lone Tree was incorporated in 1996, with a population of around 3,000. Since then the city has quadrupled in size, going from a small bedroom community of Denver to a thriving suburb. In 1997 farms occupied just 38 percent of Douglas County land.

As new towns and developments increased the county’s population, residents needed more local shopping options. In 1992 the Factory Shops, a sprawling outlet mall complex, opened in Castle Rock, and 1996 brought the opening of Park Meadows Shopping Mall in Lone Tree. The small bedroom community incorporated the same year. These developments encouraged residents to shop locally instead of traveling outside the county for purchases. It also brought needed tax revenue to the county.

Today

Currently, the largest employer in Douglas County is the retail industry, followed by government jobs. The population continues to rise, from about 175,000 in 2000 to about 319,000 in 2015. As new developments change the face of the county, residents work to balance urban and suburban growth while preserving the area’s cultural and natural heritage.

Organizations such as Historic Douglas County, Douglas County History Research Center, the Castle Rock Historical Society, the Parker Area Historical Society, and the Highlands Ranch Historical Society work to preserve significant historic buildings. In 1996, for instance, the Castle Rock Historical Society refurbished the town’s train depot and converted it into the Castle Rock Museum. Additionally, the town’s Historic Preservation Board circulates walking tour guides that take visitors past twenty-one historic sites and buildings. Douglas County also helped secure funds to restore Seventeen Mile House in 2001, and the Parker Historical Society lists an additional twenty-seven historic properties that it has helped preserve.

Douglas County also works to preserve its environment through the Pike National Forest and several state recreation sites. These sites ensure that its natural resources, such as timber and water sources—which allowed the county to be settled in the nineteenth century—can be enjoyed by generations to come.