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Rocky Mountain National Park

    Established on January 26, 1915, Rocky Mountain National Park (RMNP) has for more than a century been one of the country’s most visited national parks. Mountain vistas and wilderness solitude draw millions of people every year. The park lies between elevations of 7,000 and 14,259 feet, harboring plant communities ranging from grassland to alpine tundra as well as a host of large animals, including elk, black bear, mountain lions, bighorn sheep, and moose. The park also encompasses the headwaters of the Colorado River. Although the park offers visitors timeless snapshots of the Rocky Mountain region’s natural environments, its landscapes and ecosystems have been altered and transformed by human as well as geological processes.

    The Rockies Are Born

    Moraine ParkSeventy million years ago, the area that would become Colorado’s Front Range was covered by shallow sea water laden with silt; it was an undramatic seascape. The peaks that would eventually attract so many visitors had yet to emerge. The earliest species to call the region home were marine organisms. The range of mountains that would become the Rockies began to reveal itself around 68 million years ago. In an era that saw the extinction of the last dinosaurs, compression from westward-moving plates thrust rock and earth upward. Western North America shed its seas and the ecosystems contained within. Thus began a series of geologic upheavals that would shape the Front Range and the RMNP area into what it is today. The region would never lie underwater again, and gradually the earth began to reach upward.

    Over the next 60 million years, the Front Range was shaped and reshaped from rolling hills to small mountains through volcanic processes and erosion. Around 2 million years ago, global climate change led to the formation of glaciers. Series of glaciation and ice recession, occurring up until roughly 15,000 years ago, are primarily responsible for producing the park’s present-day scenery. Ice flows stripped rock from the earth, depositing large boulders that formed ridges. These processes formed the sheer cliffs, steep mountainsides, and deep valleys that visitors marvel at today.

    Human Arrivals

    The area’s first humans appeared a little over 10,000 years ago, around the time that relatively warm climes returned. These early hunter-gatherers likely followed the woolly mammoth into the mountainous region. Receding ice had made the area hospitable for large mammals, a transformation that would have serious implications for the region’s natural environment.

    Prehistoric peoples likely only passed through the park’s area, but there is evidence that Paleo-Indians hunted bison, elk, and deer throughout the Front Range. Some scientists posit that the Front Range became a natural refuge for early Great Plains peoples during the Holocene Climatic Optimum, an uncharacteristically warm period that began roughly 9,000 years ago and lasted two millennia. Early North Americans traversed the RMNP region to traditional hunting grounds but also found refuge in the mountains’ cooler climates. In both cases, humans were becoming integrated into the region’s ecosystems, increasingly tapping into local floral and faunal energy chains.

    Mule deer on tundraElk, deer, sheep, and bear were appealing game for seasonal hunters. Hunters in the region even constructed elaborate game-drive systems using rocks. Stones would be stacked to form low walls that gave hunters artificial cover. Remnants of these cairns still survive today. Archaeologists believe them to be roughly 5,000 years old, preceding the arrival of Native American groups known to historians. These game-drive structures are a testament to how long humans have been shaping the region’s natural environments.

    Ute and Shoshone peoples began to enter the RMNP area around 1,000 years ago. Park-like meadowlands such as present-day Estes Park became summer havens for Utes, especially those traveling to the Great Plains in search of bison. Native groups moved with the seasonal migrations of elk, traversing a variety of landscapes and altitudes in search of game. Some historians believe that the RMNP area was used by Ute people to stage a traditional spring social gathering known as the Bear Dance. The Arapaho, who arrived in the region at the turn of the nineteenth century, included the Rockies in their cosmology. They viewed the mountain range as a protective barrier, constructed to protect the Arapaho from Ute and Shoshone rivals. While Native Americans did not have permanent, year-round settlements in and around what is today RMNP, the mountains provided important resources and passageways deeply inscribed with cultural meaning.

    Permanent Settlement and Park Establishment

    In some ways, Europeans would come to have a similar relationship with the region. Parties of Spanish traders likely first entered what is now Colorado in the 1600s, and French trappers were present in the Front Range area from the 1700s and into the 1800s. But permanent settlement was not established in the RMNP area until 1859. Drawn to Colorado by the 1858–59 gold rush, Joel Estes settled in what is today Estes Park, the town directly east of RMNP. Because there was no gold in the area, Estes and his family started a cattle ranch. Throughout the late nineteenth century, whites moved into the area and reshaped its natural environments. For example, by the turn of the twentieth century elk—an important part of the park’s ecosystems today—had been hunted to extinction. They were not reintroduced to RMNP until 1913, two years before the area was designated as a national park.

    While the establishment of RMNP did help preserve thousands of acres, Congress only approved founding of the park once intensive surveys proved there was no mineral wealth to be extracted from the mountains. The park’s founding in 1915 was at some level an act of altruistic preservation, but it was also a capitalist tourist venture. Since then, the park has been integrated into an international tourist industry rooted in the availability of cheap fossil fuels, and questions have now arisen about the sustainability of tourism in RMNP. The global extraction and human consumption of coal and oil are heavy contributors to global climate change, which threatens to reshape RMNP’s ecosystems at a pace too rapid for certain species to survive. Park ecologists are already tracking changing nitrogen levels in the soil, likely the result of RMNP’s proximity to the urban-industrial Front Range. In addition, warmer temperatures allow for larger populations of tree-killing mountain pine beetles, heighten fire risk, and threaten the park’s already dwindling glaciers, which, in addition to drawing tourists, serve as key water sources for local ecosystems.

    While the area’s natural environments are in one sense protected under the national park system, those ecosystems have also been used more heavily by humans than if the area had not become a federally subsidized vacation spot. The ecosystems have also been subjected to ecological degradation originating far outside the park, sometimes quite far away; for example, dark-colored dust from Front Range development settles on snowfields in the park, attracting more heat and causing premature spring melting. Even though 2015 marked its 100-year anniversary, the constructed wilderness of RMNP faces many threats in the twenty-first century, many of which are ironically rooted in the human technologies that allow for the enjoyment of such a sublime landscape.

    John Charles Frémont (1813–90) was an American explorer for the US Topographical Engineers. He crossed Colorado on various expeditions. Between 1842 and 1853, Frémont led five western expeditions. He was involved in the Mexican-American War (1846–48) in California. Fremont became one of California’s first senators. He ran for president in 1856. Fremont also served as commander of the army’s Department of the West during the Civil War. He became wealthy through speculation in railroad development. However, Fremont lost his property and savings.

    In Colorado, Frémont’s legacy remains his expeditions. The expeditions helped map the state. They informed the national discussion about railroads to the Pacific. Fremont leant his name to such places as Fremont County and Fremont Street in Denver. In 1842, he led his first expedition to the west. Fremont began mapping the Oregon Territory. His second expedition in 1843 crossed present-day Larimer County. It led to the creation of a large map of the Oregon Territory. Frémont’s second expedition began at Westport Landing in present-day Kansas City. His goal was to continue exploring and mapping the Oregon Territory. His second objective brought him to northern Colorado.

    Northern Colorado, 1843

    There was a rumor that there was a direct route to the west though the Rocky Mountains. The route would shorten the established course along the North Platte to the Sweetwater and South Pass in present-day Wyoming. This new route was said to be up the Cache la Poudre River northwest of Fort St. Vrain. Frémont was not able to gain any useful knowledge about this passage. He knew about the Cache la Poudre River. He had crossed it in 1842.

    After getting mules and supplies at Fort St. Vrain, Frémont split his company into two groups on July 25, 1843. He sent one north with Thomas Fitzpatrick to travel west along the 1842 route. Fremont took a group northwest to find the new passage through the Rockies. He took a Shoshone woman and her two children.

    On the afternoon of July 26, 1843, he left the fort and began his search. He had trouble crossing the South Platte north of Fort St. Vrain due to heavy rains upstream. Fremont decided to rest for the evening at the confluence of the Big Thompson River and the Little Thompson. This is the present location of Milliken, Colorado. It was an evening shared with mosquitoes.

    The next morning, the group traveled along the south side of the Big Thompson. Fremont crossed the river just south of the present-day Centerra shopping area near Loveland. Continuing north he stopped at present-day Highland Meadows. There he spotted the Poudre River. He proceeded to the northwest and traveled down what is today Riverside Avenue in Fort Collins. Fremont continued along the route of what are now abandoned railroad tracks near the Fort Collins Museum of Discovery. They camped on the Poudre River just west of what is now Ted’s Place. In one day, Frémont's group traveled twenty-six miles between the Thompson Creek campsite at Milliken and their campsite on the Poudre River.

    The group ended up on the north fork of the Poudre. They traveled through what is today Eagles Nest Open Space and then west and north of Phantom Canyon. The group went through Turkey Creek Canyon north of today’s Halligan Reservoir and up onto Trail Creek.

    Frémont and his guide Kit Carson knew that they had not located the rumored passage to the west. After camping near the present Colorado-Wyoming border (Boulder Ridge), Frémont traveled into Wyoming. The group went west to present-day Albany (Douglas Reservoir/ Creek). Fremont proceeded up French Creek and over Libby Flats through the Snowy Range. The group continued across the Laramie River northwest of Saratoga in order to meet up with Fitzpatrick at Fort Hall.

    Other Expeditions

    Frémont would return to Colorado on expeditions in 1845, 1848, and 1853. In 1845, he located the headwaters of the Arkansas River near present-day Leadville. Afterwards, he went off to California. In 1848, he returned to the Rockies. Fremont was charged with finding a railroad route across the mountains. After a deadly trek through the Sangre de Cristo Mountains, Frémont led his party back to Taos, New Mexico. The group resupplied before heading to California. On his final Colorado expedition in 1853, Frémont was again sent to search for a railroad route through the Rockies. His party entered the San Luis Valley in December. They crossed the Continental Divide at Cochetopa Pass before moving on to Utah and San Francisco. After this fifth and final expedition, Frémont believed that a railroad route was possible and that it would be passable during the winter. However, the transcontinental railroad was laid through South Pass in southern Wyoming.