The Grand Canyon is a steep-sided canyon carved by the Colorado River in the United States in the state of Arizona. It is largely contained within the Grand Canyon National Park, one of the first national parks in the United States. President Theodore Roosevelt was a major proponent of preservation of the Grand Canyon area, and visited it on numerous occasions to hunt and enjoy the scenery.
The Grand Canyon is 277 miles (446 km) long, up to 18 miles (29 km) wide and attains a depth of over a mile (1.83 km) (6000 feet). Nearly two billion years of the Earth's geological history have been exposed as the Colorado River and its tributaries cut their channels through layer after layer of rock while the Colorado Plateau was uplifted. While the specific geologic processes and timing that formed the Grand Canyon are the subject of debate by geologists, recent evidence suggests the Colorado River established its course through the canyon at least 17 million years ago. Since that time, the Colorado River continued to erode and form the canyon to the point we see it at today.
Before European immigration, the area was inhabited by Native Americans who built settlements within the canyon and its many caves. The Pueblo people considered the Grand Canyon ("Ongtupqa" in Hopi language) a holy site and made pilgrimages to it. The first European known to have viewed the Grand Canyon was García López de Cárdenas from Spain, who arrived in 1540.
The Grand Canyon National Park is itself divided into two main areas: the remote North Rim and the more accessible (and therefore more crowded) South Rim. In addition, the southwestern end of the canyon is located within the borders of two Indian reservations: the Havasupai Indian Reservation and the Hualapai Indian Reservation (also known as Grand Canyon West). All of the sections of the canyon offer amenities for visitors, but the national park, and in particular the South Rim, is by far the most popular destination and the best equipped to handle the millions of yearly visitors.
Aside from casual sightseeing from the South Rim (averaging 7,000 feet [2,100 m] above sea level), rafting, hiking, running and helicopter tours are especially popular. In October 2010 the North Rim is the host to an ultramarathon. The Grand Canyon Ultra Marathon is a 78-mile (126 km) race over 24 hours. The floor of the valley is accessible by foot, muleback, or by boat or raft from upriver. Hiking down to the river and back up to the rim in one day is discouraged by park officials because of the distance, steep and rocky trails, change in elevation, and danger of heat exhaustion from the much higher temperatures at the bottom. Rescues are required annually of unsuccessful rim-to-river-to-rim travelers. Nevertheless, hundreds of fit and experienced hikers complete the trip every year.
Camping on the North and South Rims is generally restricted to established campgrounds and reservations are highly recommended, especially at the busier South Rim. There is at large camping available along many parts of the North Rim managed by Kaibab National Forest. Keep in mind North Rim campsites are only open seasonally due to road closures from weather and winter snowpack. All overnight camping below the rim requires a backcountry permit from the Backcountry Office (BCO). Each year Grand Canyon National Park receives approximately 30,000 requests for backcountry permits. The park issues 13,000 permits, and close to 40,000 people camp overnight. The earliest a permit application is accepted is the first of the month, four months before the proposed start month.
Tourists wishing for a more vertical perspective can board helicopters and small airplanes in Las Vegas, Phoenix and Grand Canyon National Park Airport (seven miles from the South Rim) for canyon flyovers. Scenic flights are no longer allowed to fly within 1500 feet of the rim within the national park because of a late 1990s crash. Maverick Helicopter offers a tour that descends and lands 3,500 feet into the Grand Canyon in Hualapai Indian Territory. The last aerial video footage from below the rim was filmed in 1984. However, some helicopter flights land on the Havasupai and Hualapai Indian Reservations within Grand Canyon (outside of the park boundaries). Recently, the Hualapai Tribe opened the glass-bottomed Grand Canyon Skywalk on their property, Grand Canyon West. The Skywalk has seen mixed reviews since the site is only accessible by driving down a 10-mile (16 km) dirt road, costs a minimum of $85 in total for reservation fees, a tour package and admission to the Skywalk itself and the fact that cameras or other personal equipment are not permitted on the Skywalk at any time due to the hazard of damaging the glass if dropped. The Skywalk is some 24 miles (39 km) west of Grand Canyon Village at the South Rim.
Lipan Point is a promontory located on the South Rim. This point is located to the east of the Grand Canyon Village along the Desert View Drive. There is a parking lot for visitors who care to drive along with the Canyon's bus service that routinely stops at the point. The trailhead to the Tanner Trail is located just before the parking lot. The view from Lipan Point shows a wide array of rock strata and the Unkar Creek area in the inner canyon.
The canyon can be seen from the Toroweap (or Tuweep) Overlook situated 3000 vertical feet above the Colorado River, about 50 miles downriver from the South Rim and 70 upriver from the Grand Canyon Skywalk. This region — “one of the most remote in the United States” according to the National Park Service — is reached only by one of three lengthy dirt tracks beginning in from St. George, Utah, Colorado City or near Pipe Spring National Monument (both in Arizona). Each road traverses wild, uninhabited land for 97, 62 and 64 miles respectively. The Park Service manages the area for primitive value with minimal improvements and services. [source : Grand Canyon]