The 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.

The Canyon is an overwhelming experience, and nothing can prepare a visitor for the sight. The Grand Canyon is a massive canyon carved over several million years by the Colorado River. Grand Canyon National Park boasts an elevation change of nearly 7,000 feet (2130 m) from Point Imperial (at nearly 9,000 feet or 2740 m) to the banks of Lake Mead (at just over 2,000 feet or 610 m). The canyon itself is, from rim to river over a mile (1610 m) deep. In spots the rock layers exposed in the canyon display over two billion years of geologic history.

The park was founded as Grand Canyon National Monument in 1908 by President Theodore Roosevelt, and became a national park in 1919. Today the park contains over 1.2 million acres (490,000 ha), slightly less than the entire state of Delaware, and in 2004 received more than 4.3 million visitors.

Throughout the past century, hundreds of authors have attempted to depict the enormous landscape that is Grand Canyon. Not surprisingly, words most often fail to invoke the sense of awe and wonder that many visitors experience. Edward Abbey, a noted Southwest author, once penned: "Those who love it call it the canyon. The canyon. As if there were no other topographic feature on the face of the Earth".

There are, of course, other canyons on the planet. Some are longer, others wider, and even some that are deeper. Canyon visitors are often surprised to learn that Grand Canyon sets no records for sheer size. It is, however, simply regarded by most as the "grandest" canyon of them all.

Geologically, the canyon extends from Lee's Ferry near the Arizona/Utah border to the Grand Wash Cliffs near Las Vegas, a distance of 277 mi (445 km). It ranges in width from about a quarter mile to over 18 mi (29 km) wide. In places the canyon is over a mile deep.

However, it is not the statistics that define this landscape as "grand", but rather a combination of factors. The desert environment and a lack of herbaceous ground cover reveal a geologic story that is unparalleled. Surprisingly, the rock layers displayed at Grand Canyon show little sign of wear. The layers have been preserved almost perfectly, as though they were layers in a cake. Nowhere else on Earth displays so many volumes of the planet's history in such pristine condition.

The resulting landscape provides visitors with some of the most magnificent and unsurpassed vistas on the planet.