Grand Canyon National Park

Arizona's Grand Canyon is not the largest, nor the longest, nor the deepest canyon in the world. However, the gorge cut ages ago by the Colorado River earns its name not from its size, but from its spectacular beauty and awe-inspiring vistas. And, it's still unimaginably large. In fact, the canyon is so big that one can usually find a peaceful spot to contemplate this behemoth of a landmark, even with five million visitors a year at Grand Canyon National Park.

The colorful layers of rocks exposed in the Grand Canyon are old, 2000 million years by some estimates. The park itself seems infantile by those standards, although it is actually one of the oldest national parks in the country, designated as such in 1919, three years after the creation of the National Park Service. However, it was first afforded federal protection in 1893 as a Forest Reserve and later as a National Monument. The stream of visitors has been steady ever since, with most arriving at the South Rim,30 miles of which is accessible by park roads. For those wanting to forego air-conditioning, the Grand Canyon offers amazing hiking, from short loops on well-maintained trails to serious and lengthy treks through the wilderness.