The Laramie Mountains are a

range Range may refer to: Geography * Range (geographic), a chain of hills or mountains; a somewhat linear, complex mountainous or hilly area (cordillera, sierra) ** Mountain range, a group of mountains bordered by lowlands * Range, a term used to i ...

of moderately high peaks on the eastern edge of the

Rocky Mountains The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch in great-circle distance, straight-line distance from the northernmost part of Western Can ...

in the U.S states of

Wyoming Wyoming ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States, Western United States. It borders Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho t ...

and

Colorado Colorado is a U.S. state, state in the Western United States. It is one of the Mountain states, sharing the Four Corners region with Arizona, New Mexico, and Utah. It is also bordered by Wyoming to the north, Nebraska to the northeast, Kansas ...

. The range is the northernmost extension of the line of the ranges along the eastern side of the Rockies, and in particular of the higher peaks of the

Front Range The Front Range is a mountain range of the Southern Rocky Mountains of North America located in the central portion of the U.S. State of Colorado, and southeastern portion of the U.S. State of Wyoming. It is the first mountain range encounter ...

directly to the south. North of the range, the gap between the Laramie range and the

Bighorn Mountains The Bighorn Mountains ( or ) are a mountain range in northern Wyoming and southern Montana in the United States, forming a northwest-trending spur from the Rocky Mountains extending approximately northward on the Great Plains. They are separa ...

provided the route for historical trails, such as the

Oregon Trail The Oregon Trail was a east–west, large-wheeled wagon route and Westward Expansion Trails, emigrant trail in North America that connected the Missouri River to valleys in Oregon Territory. The eastern part of the Oregon Trail crossed what ...

, the

Mormon Trail The Mormon Trail is the route from Illinois to Utah on which Mormon pioneers (members of the Church of Jesus Christ of Latter-day Saints) traveled from 1846 to 1869. Today, the Mormon Trail is a part of the United States National Trails Syst ...

, and the

Pony Express The Pony Express was an American express mail service that used relays of horse-mounted riders between Missouri and California. It was operated by the Central Overland California and Pikes Peak Express Company. During its 18 months of opera ...

. The Laramie Mountains begin in northern Colorado and extend discontinuously into southeastern Wyoming between

Cheyenne The Cheyenne ( ) are an Indigenous people of the Great Plains. The Cheyenne comprise two Native American tribes, the Só'taeo'o or Só'taétaneo'o (more commonly spelled as Suhtai or Sutaio) and the (also spelled Tsitsistas, The term for th ...

and Laramie and northward to Casper. (By some definitions the Laramies are only in Wyoming.) They are named after the Laramie River, which cuts through the range from southwest to northeast and joins the

North Platte River The North Platte River is a major tributary of the Platte River and is approximately long, counting its many curves.U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map accessed March 21, 2011 I ...

east of the range in eastern Wyoming. The mountains in turn give their name to the

Laramide orogeny The Laramide orogeny was a time period of mountain building in western North America, which started in the Late Cretaceous, 80 to 70 million years ago, and ended 55 to 35 million years ago. The exact duration and ages of beginning and end of the o ...

, the uplift of the North American Plate approximately 70 million years ago that created the present Rocky Mountains. The highest portions of the Laramie mountains are mostly in public ownership, forming part of the Medicine Bow-Routt and Roosevelt National Forests.

Geography

The mountains consist of a series of

Precambrian The Precambrian ( ; or pre-Cambrian, sometimes abbreviated pC, or Cryptozoic) is the earliest part of Earth's history, set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian, the first period of t ...

Sherman

granite Granite ( ) is a coarse-grained (phanerite, phaneritic) intrusive rock, intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly coo ...

monadnock An inselberg or monadnock ( ) is an isolated rock hill, knob, ridge, or small mountain that rises abruptly from a gently sloping or virtually level surrounding plain. In Southern Africa, a similar formation of granite is known as a koppie, an ...

s rising above a broad

erosion surface In geology and geomorphology, an erosion surface is a surface of rock (geology), rock or regolith that was formed by erosion and not by construction (e.g. lava flows, sediment deposition) nor fault (geology), fault displacement. Erosional surfaces ...

that form extensive unwooded parks whose surfaces are generally at about above sea level. The high peaks of the range, which are much lower than those commonly associated with the Rocky Mountains, rise abruptly above the surrounding

peneplain In geomorphology and geology, a peneplain is a low-relief plain formed by protracted erosion. This is the definition in the broadest of terms, albeit with frequency the usage of peneplain is meant to imply the representation of a near-final (or ...

to altitudes between and above sea level, with the exceptions of Laramie Peak in Wyoming which tops out at and South Bald Mountain in Colorado rising to . The granitic soils were formed from the erosion of the surrounding monadnocks and have an effective depth of less than . Three principal

life zone The life zone concept was developed by C. Hart Merriam in 1889 as a means of describing areas with similar plant and animal communities. Merriam observed that the changes in these communities with an increase in latitude at a constant elevation a ...

s are represented in the Laramies: Upper Sonoran, Transition and Canadian.Carpenter, J. R. 1956. An Ecological Glossary. Hafner, NY. Some early sources indicated that the Hudsonian Zone occurs on Laramie Peak but there is nothing distinctive about either the flora or fauna on the top of this peak, for it consists of nothing but a large granite outcrop. On the eastern and north eastern slopes of the range the prairie/mountain transition is very gentle at the south end (between Cheyenne and Laramie) and much more abrupt and broken farther north. The elevation is lowest, about (1370 m), along the

. On the western slopes the total relief is much less, as the floors of the three

intermontane Intermontane is a physiographic adjective formed from the prefix " inter-" (''signifying among, between, amid, during, within, mutual, reciprocal'') and the adjective "montane" (inhabiting, or growing in mountainous regions, especially cool, mo ...

basins Basin may refer to: Geography and geology * Depression (geology) ** Back-arc basin, a submarine feature associated with island arcs and subduction zones ** Debris basin, designed to prevent damage from debris flow ** Drainage basin (hydrology), ...

that border the Laramies on this side (Shirley, Hanna and Laramie basins) rarely drop below . An extensive high plain and semi-desert extends from the Laramie Mountains south west as far as the Shirley Mountains. The Laramie Basin separates the Laramie Mountains from the Medicine Bow Mountains to the south and west, and its floor is above except for a few depressions and blowouts (such as Cooper Lake). The Laramie Mountains are bisected by the Laramie River, which cuts a canyon through the mountains roughly due west of Wheatland, and then continues its generally eastward course to join the North Platte River near the town of Fort Laramie. The division marks the southern end of the continuous coniferous forest in the range, and separates the range into two parts. The southern part is generally drier and much more open, with little or no forest except for the southern end at Pole Mountain and surrounding area, where the interesting granite outcrops at Vedauwoo provide climbing practice and grand picnic scenery. The range is prominently visible from

Interstate 25 Interstate 25 (I-25), also known as the Pan-American Freeway, is a major Interstate Highway in the western United States. It is primarily a north–south highway, serving as the main route through New Mexico, Colorado, and Wyoming. I-25 st ...

between Casper and Cheyenne.

Interstate 80 Interstate 80 (I-80) is an east–west transcontinental freeway that crosses the United States from San Francisco, California, to Teaneck, New Jersey, in the New York metropolitan area. The highway was designated in 1956 as one of the ori ...

and the

Union Pacific Railroad The Union Pacific Railroad is a Railroad classes, Class I freight-hauling railroad that operates 8,300 locomotives over routes in 23 U.S. states west of Chicago and New Orleans. Union Pacific is the second largest railroad in the United Stat ...

cross the range between Cheyenne and Laramie on an outlying ramp of the High Plains called the "Gangplank".

References

External links

* {{Coord, 41, 38, N, 105, 40, W, display=title Mountain ranges of Colorado Mountain ranges of Wyoming Ranges of the Rocky Mountains North American Cordillera Landforms of Laramie County, Wyoming Landforms of Albany County, Wyoming Landforms of Natrona County, Wyoming Landforms of Larimer County, Colorado

Geography

See also

References

Further reading

External links