A 277-mile, mile-deep gorge in northern Arizona, carved by the Colorado River — and one of the most studied landscapes on Earth.
The Grand Canyon is a steep-sided canyon carved by the Colorado River in northern Arizona, United States. It is 277 miles (446 km) long, up to 18 miles (29 km) wide, and attains a depth of over a mile (about 6,000 feet / 1,800 m).
The Grand Canyon exposes one of the most complete vertical slices of rock on the planet. From the Colorado River at the bottom of the Inner Gorge — the dark, twisted Vishnu Basement Rocks, metamorphosed sediments intruded by granite about 1.8 billion years ago — the walls climb upward through layer after named layer: the Zoroaster Granite intruded into those sediments roughly 1.4 billion years ago; the tilted Grand Canyon Supergroup sandstones and limestones sit at an angle on top; and above them, in horizontal sheets, the unmistakable layer-cake sequence begins.
The most-visited sequence is the Grand Staircase of sedimentary rocks above the basement: the Tapeats Sandstone (about 540 million years old, a beach and shallow sea deposit); the Bright Angel Shale and Muav Limestone (a deeper marine setting, rich in trilobite fossils); the Temple Butte Formation; the cliff-and-slope Tonto Group; the massive Redwall Limestone (which is grey, despite the name, and often stained red by iron oxides washing down from above); the Supai Group (four shales-and-limestones that were laid down as river deltas and tidal flats, roughly 320–285 million years ago); the soft, dun-colored Hermit Shale; the cream-to-pink Coconino Sandstone (cross-bedded dunes of an ancient Sahara-like desert); the Toroweap Formation; and the rim-capping Kaibab Limestone, about 270 million years old.
Read that as one long slow story: an ancient ocean rose and fell; a Sahara-like desert spread across the region; rivers meandered and flooded; swamps and shallow seas returned. Each of those environments left its own fingerprint in stone, and the canyon is the rare place where all of them are visible at once, in a single 5,000-foot wall.
There is a long-running and surprisingly contested scientific question here: when did the Colorado River cut down through those layers to make the canyon we see? Older work assumed a young canyon, perhaps 6 million years old; newer research argues parts of the eastern canyon are much older (30–70 million years), and that the river arrived in different sections at different times.
The most cited recent estimate (from work published by researchers at the California Institute of Technology, the University of Colorado Boulder, and the U.S. Geological Survey, summarized in Science in 2008) is that the river began carving the western Grand Canyon about 6 million years ago, while a different ancestral river system cut a separate, older canyon in the eastern section. The two eventually linked up. Even the conservative 6-million-year number is geologically fast: a mile of rock removed, mostly by the river and its tributaries, in just a few million years.
The Colorado River is still doing the work. It drops about 2,200 feet (670 m) across the canyon's length — a slope of roughly 8 feet per mile — and that gradient, plus a heavy summer-monsoon and snowmelt cycle, is what makes it such an aggressive cutter.
Humans have lived in and around the Grand Canyon for at least 12,000 years. Ancestral Puebloan people occupied the rim and inner-canyon sites from roughly 1,000 to 700 years ago; the Cohonina, the Cerbat, and the ancestors of the modern Havasupai and Hualapai have a continuous record on the southern and western plateaus. The Havasupai ("people of the blue-green waters") still live in the only community inside the canyon, at Supai, Arizona, on the floor of Cataract Canyon on the Havasupai Reservation. Mail to Supai is still delivered by mule.
European-American exploration began in 1869, when Major John Wesley Powell — a one-armed Civil War veteran and geologist — led nine men in four wooden boats down the uncharted Green and Colorado rivers. Three men left the expedition before the run; four of the remaining six disappeared in the Separation Canyon area and are believed to have been killed by Shivwits Paiute. The rest emerged, emaciated, three months later at the mouth of the Virgin River. Powell returned in 1871 and 1872 with full government backing; his journals, especially the 1875 Exploration of the Colorado River and Its Canyons, are still in print and remain some of the most readable science writing of the 19th century.
President Theodore Roosevelt visited the canyon in 1903, called it "one of the great sights every American should see," and pushed Congress to protect it as a national monument in 1908. The monument became Grand Canyon National Park on February 26, 1919, in the same legislation that also created the National Park Service era of conservation policy in the American West.
The park covers 1,217,262 acres (about 1,900 square miles) — most of it backcountry, only a fraction developed for visitors. About 6 million people a year visit; roughly 90% of them go to the South Rim, which is open every day of the year and is the home of Grand Canyon Village, the historic El Tovar Hotel, the Bright Angel Lodge, the depot for the Grand Canyon Railway, and the shuttle-bus system that connects the viewpoints and trailheads.
The most visited viewpoints, all reachable by a free shuttle bus from the visitor center, are Mather Point (the classic first stop, especially at sunrise), Yavapai Point (the best single view of the Colorado River far below), Hopi Point (famous for sunsets and for the way the light rakes across the canyon), and Moran Point (the painting point — Thomas Moran painted here in 1873, and the view is essentially unchanged). Bright Angel Point on the North Rim is the most common North Rim view, and Desert View, the easternmost South Rim lookout, has a 70-foot stone watchtower built in 1932 by architect Mary Colter.
Below the rim, the main corridor trails are the Bright Angel Trail and the South Kaibab Trail, both dropping roughly 4,500 vertical feet from rim to river. The standard warning from the Park Service is real: do not try to hike to the river and back in a single day in summer. The temperature on the rim can be 30 degrees cooler than the inner canyon, and people die every year from heat exhaustion and dehydration on the corridor trails. The Park Service tracks and reports every fatality; the long-running total is sobering.
The Grand Canyon has five of the seven North American "life zones" (only the tropical and subarctic are missing), which is one of the reasons biologists consider it a single ecosystem worth protecting. On the South Rim you can reliably see mule deer, the bright-orange Abert's squirrel, common ravens, and Steller's jays. Elk, reintroduced to the South Rim in the early 20th century, are now treated as an overabundant invasive on the North Rim where they overgraze the meadows. California condors were reintroduced in 1996 and the canyon now holds one of the largest wild populations; condors are tagged with numbered tags and can sometimes be seen soaring from the rim, with wingspans up to 9.5 feet.
The river itself harbors the endemic Humpback Chub, a 4-to-8-inch minnow found in only a few Colorado River tributaries and protected under the Endangered Species Act. Bighorn sheep live on the steep talus slopes of the inner canyon, where their hooves can grip surfaces that look entirely unclimbable. Mountain lions are present throughout the park but are rarely seen; black bear sightings have increased on the South Rim in the last decade.
| Length | 277 miles (446 km) |
| Width | up to 18 miles (29 km) |
| Depth | over 1 mile (~6,000 ft / 1,800 m) |
| Established | National Park on Feb 26, 1919 (monument 1908) |
| Annual visitors | ~6 million (pre-2020 baseline) |
| Oldest exposed rock | ~1.8 billion years (Vishnu Basement Rocks) |
Every fact verified on the Wikipedia article on the Grand Canyon.
"Grand Canyon National Park — 4K Documentary Film with Narration" by 4K Relaxation Channel.
"Grand Canyon National Park of Arizona — 4K Nature Documentary Film. Episode 2" by 4K Relaxation Channel.
"Grand Canyon 4K" by Around The World 4K.
Map data © OpenStreetMap contributors. Centered on the South Rim, Grand Canyon Village area (36.1°N, 112.1°W). Open full map in a new tab.
Some of the most-quoted words ever written about the Grand Canyon came from people who stood on the rim. President Theodore Roosevelt, after visiting in 1903, said: "In the Grand Canyon, Arizona has a natural wonder which, so far as I know, is in kind absolutely unparalleled throughout the rest of the world." Poet and essayist John Muir wrote after his visit: "The Grand Canyon is a sort of landscape painting that Nature paints with the sun." Both quotes are widely published in park histories and the National Park Service's own materials.
Modern travel writers keep making essentially the same point. National Geographic assays the canyon "one of the most extraordinary landscapes on Earth," and its visitor guides have long described the South Rim viewpoints as the classic first-time experience; guidebooks from Lonely Planet and Rough Guides consistently rank the canyon among the top must-see national parks in the American West, largely for the way the scale and the color and the silence combine. The canyon also consistently appears on TripAdvisor's lists of the world's most-reviewed and highest-rated attractions — millions of visitors have recorded their own reviews there.
We keep quotes short and attributed. Live user reviews on TripAdvisor and Yelp change constantly and are best read (and quoted) at the original source — links above: TripAdvisor review page and Yelp listing. If you have a favorite review you'd like featured here, we're happy to add it.