Glenwood Canyon is a rugged scenic canyon in western

Colorado Colorado (, other variants) is a state in the Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the western edge of the ...

in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country Continental United States, primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., ...

. Its walls climb as high as above the

Colorado River The Colorado River ( es, Río Colorado) is one of the principal rivers (along with the Rio Grande) in the Southwestern United States and northern Mexico. The river drains an expansive, arid watershed that encompasses parts of seven U.S. s ...

. It is the largest such canyon on the Upper Colorado. The canyon, which has historically provided the routes of

railroad Rail transport (also known as train transport) is a means of transport that transfers passengers and goods on wheeled vehicles running on rails, which are incorporated in tracks. In contrast to road transport, where the vehicles run on a prep ...

s and

highway A highway is any public or private road or other public way on land. It is used for major roads, but also includes other public roads and public tracks. In some areas of the United States, it is used as an equivalent term to controlled-access ...

s through western Colorado, currently furnishes the routes of

Interstate 70 Interstate 70 (I-70) is a major east–west Interstate Highway in the United States that runs from I-15 near Cove Fort, Utah, to a park and ride lot just east of I-695 in Baltimore, Maryland, and is the fifth-longest Interstate in the co ...

and the

Union Pacific The Union Pacific Railroad , legally Union Pacific Railroad Company and often called simply Union Pacific, is a freight-hauling railroad that operates 8,300 locomotives over routes in 23 U.S. states west of Chicago and New Orleans. Union Pac ...

's Central Corridor between

Denver Denver () is a consolidated city and county, the capital, and most populous city of the U.S. state of Colorado. Its population was 715,522 at the 2020 census, a 19.22% increase since 2010. It is the 19th-most populous city in the Unit ...

and Grand Junction.

Location

California Zephyr--Eastbound meets Westbound in Glenwood Canyon

The canyon stretches from near Dotsero, where the Colorado receives the Eagle River, downstream in a west-southwest direction to just east of

Glenwood Springs Glenwood Springs is a home rule municipality that is the county seat of Garfield County, Colorado, United States. The city population was 9,963 at the 2020 United States Census. Glenwood Springs is located at the confluence of the Roaring Fork ...

, on the mouth of the Roaring Fork. Most of the canyon is in Garfield County, with the upper portion near Dotsero lying in Eagle County.

Geology

The canyon was formed relatively recently in

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...

time by the rapid cutting of the Colorado down through layers of

sedimentary rock Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface, followed by cementation. Sedimentation is the collective name for processes that cause these particles ...

. The upper layers of the canyon are

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicat ...

from Pennsylvanian and Mississippian. Sections of the lower canyon walls are made of

Cambrian The Cambrian Period ( ; sometimes symbolized Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million years ago ...

rock. The Mississippian layer that is prominent throughout much of the upper rim sections of the canyon is part of the

Leadville Formation The City of Leadville is a statutory city that is the county seat, the most populous community, and the only incorporated municipality in Lake County, Colorado, United States. The city population was 2,602 at the 2010 census and an estimated ...

Railroads

In 1906, the canyon provided the route of the

Taylor State Road Taylor, Taylors or Taylor's may refer to: People * Taylor (surname) ** List of people with surname Taylor * Taylor (given name), including Tayla and Taylah * Taylor sept, a branch of Scottish clan Cameron * Justice Taylor (disambiguation) ...

, a

gravel road A gravel road is a type of unpaved road surfaced with gravel that has been brought to the site from a quarry or stream bed. They are common in less-developed nations, and also in the rural areas of developed nations such as Canada and the Unit ...

that was the first route for

automobile A car or automobile is a motor vehicle with wheels. Most definitions of ''cars'' say that they run primarily on roads, seat one to eight people, have four wheels, and mainly transport people instead of goods. The year 1886 is regarded ...

s through the Colorado Rockies. The canyon also provided the route for the

Denver and Rio Grande Western Railroad The Denver & Rio Grande Western Railroad , often shortened to ''Rio Grande'', D&RG or D&RGW, formerly the Denver & Rio Grande Railroad, was an American Class I railroad company. The railroad started as a narrow-gauge line running south from De ...

in the late 19th century. Through acquisitions, the line is currently part of the

system, comprising part of its Central Corridor between

and Grand Junction. As Glenwood Canyon was one of the iconic scenic views along the ''

California Zephyr The ''California Zephyr'' is a passenger train operated by Amtrak between Chicago and the San Francisco Bay Area (at Emeryville), via Omaha, Denver, Salt Lake City, and Reno. At , it is Amtrak's longest daily route, and second-longest overall ...

'' passenger train, a

monument A monument is a type of structure that was explicitly created to commemorate a person or event, or which has become relevant to a social group as a part of their remembrance of historic times or cultural heritage, due to its artistic, hist ...

to the dome car design was originally installed in the canyon. In the 1990s, the monument was relocated to the

Colorado Railroad Museum The Colorado Railroad Museum is a non-profit railroad museum. The museum is located on at a point where Clear Creek flows between North and South Table Mountains in Golden, Colorado. The museum was established in 1959 to preserve a record of ...

in Golden to make way for the construction on

Interstate 70

The canyon is widely considered one of the most scenic natural features on the

Interstate Highway System The Dwight D. Eisenhower National System of Interstate and Defense Highways, commonly known as the Interstate Highway System, is a network of controlled-access highways that forms part of the National Highway System in the United States. T ...

of the United States. Foot access to the canyon is available at four rest areas along Interstate 70 in the canyon. The Hanging Lake

Rest Area A rest area is a public facility located next to a large thoroughfare such as a motorway, expressway, or highway, at which drivers and passengers can rest, eat, or refuel without exiting onto secondary roads. Other names include motorway serv ...

(exit 125) provides access to the canyon along a stretch where I-70 is concealed in the Hanging Lake Tunnel. The freeway is also prone to

rockslide A rockslide is a type of landslide caused by rock failure in which part of the bedding plane of failure passes through compacted rock and material collapses ''en masse'' and not in individual blocks. Note that a rockslide is similar to an avalanc ...

s in the canyon, such as the ones that closed it in February 2016 and July 2021.

References

*''Roadside Geology of Colorado'' by Halka Chronic (1980).

External links