| Arthur's Rock | |
|---|---|
 Arthur's Rock rises steeply from the Great Plains in Lory State Park outside of Fort Collins, Colorado. The rock that composes it is over 1.7 billion years old (August 31st, 2023) | |
| Highest point | |
| Elevation | 2,066.544 m (6,780.00 ft) |
| Coordinates | 40°34′06″N105°11′17″W / 40.56828°N 105.18813°W |
| Geography | |
  Arthur's Rock | |
Arthur's Rock is a 6,780 foot (2,066.5 meter) pillar in the foothills of the Colorado Front Range, near Fort Collins, Colorado. [1]
The name "Arthur's Rock" comes from Arthur Howard, who owned the rock and its surroundings before the establishment of Lory State Park. [2]
Arthur's Rock is located directly outside of downtown Fort Collins, Colorado and is easily visible from much of the town and the campus of Colorado State University.
It is located within Lory State Park, a 2,574 acre wilderness park comprising the western side of Horsetooth Reservoir. A number of single track hiking and biking trails provide access to the summit and surroundings of Arthur's Rock. The trail to the top of the rock is among the most popular in the park. [3]
The area receives a moderate amount of snowfall between the months of October and May.
Similar to nearby Horsetooth Mountain, Arthur's Rock is composed of 1.7 billion year-old pegmatite, a type of intrusive igneous rock.
The rock that now forms the summit was originally a subterranean pluton, a part of the wider Log Cabin Batholith that covers much of the area currently. Over the millennia, layers of sedimentary rock have been eroded away, leaving the hard pegmatite exposed. [4] This rock is exceptionally old.
Arthur's Rock exists at the intersection between the shortgrass prairie of the Great Plains and the Pinyon–juniper woodland of the Front Range Foothills. [5] Higher elevations on the mountain show species characteristic of montane ecosystems like blue spruce.
Lower elevations in the area of the mountain are host to prairies composed of Blue Grama (Bouteloua gracilis), Buffalo Grass (Bouteloua dactyloides) and Western Wheatgrass (Pascopyrum smithii). Rabbitbrush, sagebrush and prickly pear (Opuntia sp.) are common among grasses. [6]
A number of wildflowers occur on and around Arthur's Rock like yarrow (Achillea millefolium), prairie sunflower (Helianthus petiolaris), common sunflower (Helianthus annuus), prairie bluebell (Mertensia lanceolata) and Rocky Mountain bee plant (Cleomella serrulata).
Fort Collins is a home rule municipality that is the county seat and the most populous municipality of Larimer County, Colorado, United States. The city population was 169,810 at the 2020 census, an increase of 17.94% since 2010. Fort Collins is the principal city of the Fort Collins, CO Metropolitan Statistical Area and is a major city of the Front Range Urban Corridor. The city is the fourth most populous city in Colorado. Situated on the Cache La Poudre River along the Colorado Front Range, Fort Collins is located 56 mi (90 km) north of the Colorado State Capitol in Denver.
Larimer County is a county located in the U.S. state of Colorado. As of the 2020 census, the population was 359,066. The county seat and most populous city is Fort Collins. The county was named for William Larimer, Jr., the founder of Denver.
The Cache la Poudre River, also known as the Poudre River, is a river in the state of Colorado in the United States.
Horsetooth Mountain is a mountain summit in the foothills of the Front Range of the Rocky Mountains of North America. The 7,259-foot (2,213 m) peak is located in the Horsetooth Mountain Open Space, 7.0 miles (11.2 km) west of downtown Fort Collins in Larimer County, Colorado, United States.
The Big Thompson River is a tributary of the South Platte River, approximately 78 miles (126 km) long, in the U.S. state of Colorado. Originating in Forest Canyon in Rocky Mountain National Park, the river flows into Lake Estes in the town of Estes Park and then through Big Thompson Canyon. It includes four crossings/bridges which are listed on the U.S. National Register of Historic Places.
Mount Blue Sky is the highest peak in the Mount Evans Wilderness in the Front Range of the Rocky Mountains of North America. The prominent 14,266.1-foot (4,348 m) fourteener is located 13.4 miles (21.6 km) southwest by south of Idaho Springs in Clear Creek County, Colorado, United States, on the drainage divide between Clear Creek in Arapaho National Forest and the North Fork South Platte River in Pike National Forest.
The Poudre Canyon is a narrow verdant canyon, approximately 40 miles (64 km) long, on the upper Cache la Poudre River in Larimer County, Colorado in the United States. The canyon is a glacier-formed valley through the foothills of the Front Range of the Rocky Mountains northwest of Fort Collins.
Bellvue is an unincorporated community and U.S. Post Office in Larimer County, Colorado. It is a small agricultural community located in Pleasant Valley, a narrow valley just northwest of Fort Collins near the mouth of the Poudre Canyon between the Dakota Hogback ridge and the foothills of the Rocky Mountains. The ZIP Code of the Bellvue Post Office is 80512.
Horsetooth Reservoir is a large reservoir in southern Larimer County, Colorado, in the foothills just west of the city of Fort Collins, Colorado. The reservoir runs north-south for approximately 6.5 miles (10 km) and is approximately one-half mile (1 km) wide. Its shape and orientation are the result of the fact that the main body of the reservoir is contained between several homoclinal ridges. A ridge composed of Dakota sandstone runs along the east side where gaps in the ridge are plugged by dams. On the west (uphill) side there are two prominent ridges topped by erosion-resistant sandstones of the Lyons and Ingleside formations. Gaps in these ridges have created a handful of bays and coves the largest of which is Inlet Bay, home to a marina and campgrounds.
Pikes Peak granite is a 1.08 billion year old Late-Precambrian geologic formation found in the central part of the Front Range of Colorado. It is a coarse-grained pink to light red syenogranite with minor gray monzogranite, and it has a distinctive brick-red appearance where it outcrops. The granite gets its name from the 14,115-foot (4,302 m) Pikes Peak, which is made up almost entirely of this rock.
The Colorado–Big Thompson Project is a federal water diversion project in Colorado designed to collect West Slope mountain water from the headwaters of the Colorado River and divert it to Colorado's Front Range and plains. In Colorado, approximately 80% of the state's precipitation falls on the West Slope, in the Rocky Mountains, while around 80% of the state's growing population lives along the eastern slope, between the cities of Fort Collins and Pueblo.
Bouteloua dactyloides, commonly known as buffalograss or buffalo grass, is a North American prairie grass native to Canada, Mexico, and the United States. It is a short grass found mainly on the High Plains and is co-dominant with blue grama over most of the shortgrass prairie. Buffalo grass in North America is not the same species of grass commonly known as "buffalo" in Australia.
Spring Creek is a 12.7-mile-long (20.4 km) tributary of the Cache La Poudre River in the state of Colorado in the United States.
The shortgrass prairie is an ecosystem located in the Great Plains of North America. The two most dominant grasses in the shortgrass prairie are blue grama and buffalograss, the two less dominant grasses in the prairie are greasegrass and sideoats grama. The prairie was formerly maintained by grazing pressure of American bison, which is the keystone species. Due to its semiarid climate, the shortgrass prairie receives on average less precipitation than that of the tall and mixed grass prairies to the east.
Lory State Park, is a state park located west of the city of Fort Collins, Colorado and is west of Horsetooth Reservoir and north of Horsetooth Mountain Park. Some of the park's more popular attractions include mountain biking, hiking, horseback riding and rock climbing. The park also contains its own bike park, which features dirt jumping, a pump track, and a skills area.
Pinyon–juniper woodland, also spelled piñon–juniper woodland, is a biome found mid-elevations in arid regions of the Western United States, characterized by being an open forest dominated by low, bushy, evergreen junipers, pinyon pines, and their associates. At lower elevations, junipers often predominate and trees are spaced widely, bordering on and mingling with grassland or shrubland, but as elevation increases, pinyon pines become common and trees grow closer, forming denser canopies. Historically, pinyon-juniper woodland provided a vital source of fuel and food for indigenous peoples of the American Southwest. The nuts continue to be a traditional indigenous food, and because nut-collecting was also adopted by the Spanish in the 1500s, the nuts are also traditionally harvested by some Hispanic communities.
The Idaho Batholith ecoregion is a Level III ecoregion designated by the United States Environmental Protection Agency (EPA) in the U.S. states of Idaho and Montana. It is contained within the following biomes designated by the World Wild Fund for Nature (WWF): temperate coniferous forests; temperate grasslands, savannas, and shrublands; and deserts and xeric shrublands.
Margaret B. Fuller Boos was an influential actor in the study of pegmatite geology. Although she did not begin her career in the study of pegmatite, it became her niche as her career developed. Boos spent a large portion of her life throughout the Colorado Rockies. Through her many years of fieldwork, she was most noted for her ability to map a large proportion of the Front Rage in Colorado with the help of her husband, Charles Maynard Boos.
Alexander Mountain is a mountain in Larimer County, Colorado named for the pioneers John and Grant Alexander. It is within a mid-elevation ponderosa pine forest in the Canyon Lakes Ranger District of the Roosevelt National Forest with mountain mahogany, skunkbrush, and gambel oak forbs. North of US Highway 34 between Loveland and Estes Park, west of Green Ridge, and east of Cedar Creek, it is recognizable by its pyramidal shaped south face. Its habitat is mesic and dry-mesic and has cliff faces which are home to rattlesnakes. Now home to the Sylvan Dale Guest Ranch, its cultural significance is the final stand in a bear hunt in the memoirs of Gerry Spence. On July 29, 2024, an unknown ignition of a hot dry remote area on the north face of the Alexander Mountain caused the Alexander Mountain Fire, receiving national attention for a rapidly accelerating wildfire causing a wide evacuation area under volatile circumstances and risking losses to communication and energy infrastructure as well as ranching and tourism communities along the Big Thompson River near Drake, Colorado.