The Grand Canyon is in the northwest corner of Arizona, close to the borders of Utah and Nevada. The Colorado River, which flows through the canyon, drains water from seven states, but the feature we know as Grand Canyon is entirely in Arizona.

The park includes over a million acres of land: 1,218,376 acres/493,077 hectares, or 1,904 square miles/4931 square km. Most people measure the canyon in Colorado River miles. By that standard, Grand Canyon is 277 miles/446 km long. It begins at Lees Ferry and ends at Grand Wash Cliffs.

The Colorado River is longer than Grand Canyon, flowing 1450 miles/2333 km from the Rocky Mountains of Colorado to the Gulf of California in Mexico. Grand Canyon is only one of many beautiful canyons carved by the river. Others include Cataract Canyon and Glen Canyon, the latter now lying beneath the waters of Lake Powell. Most people agree, however, that Grand Canyon is the most spectacular. No other place in the world looks quite like it.

Width and depth of the canyon vary from place to place. At the South Rim, near Grand Canyon Village, it's a vertical mile (about 5000 feet/1524 m) from rim to river, or 7 miles/11.3 km by trail. At its deepest, it is 6000 vertical feet/1829 m from rim to river. The width of the canyon at Grand Canyon Village is 10 miles/16 km (rim to rim), though in places it is as much as 18 miles/29 km wide.¹

^{1.  National Park Service, Grand Canyon National Park, Quick Look at Grand Canyon National Park, accessed on 10 March 2002, available from http://www.nps.gov/grca/grandcanyon/quicklook/index.htm}