The Grand Canyon

The Grand Canyon runs 277 miles, is up to 18 miles across, and drops more than a mile at its deepest, 6,093 feet. Its walls read as geology in layers. The Kaibab Limestone at the rim is about 270 million years old, and the dark Vishnu Schist at the bottom of the inner gorge is nearly two billion. The Colorado River did the cutting.

Visiting on May 6, 1903, Theodore Roosevelt said: "Leave it as it is. You cannot improve on it; not a bit. The ages have been at work on it, and man can only mar it." He declared it a national monument on January 11, 1908. Congress made it a national park, and Woodrow Wilson signed the act, on February 26, 1919.

In the picture, the last sun lights the upper terraces in orange and red while the lower ledges fall to violet. A silver ribbon of river winds in at the lower right, and a lone, gnarled pine holds the left edge of the rim. Streaks of pink and gold run across the top of the sky.