The Painted Desert is a picturesque and extraordinarily colorful landscape located in the north-central area of Arizona in the United States. It is about 160 miles (258 km) long, with widths ranging from 10-35 miles (16-56 km) and is about 146 square miles (378 square km) in total area. This landscape formation runs from the Grand Canyon southeast along the Colorado and Little Colorado rivers to somewhat beyond the Petrified Forest National Park. Elevations within the Painted Desert range from about 4,500-6,500 feet (1,370-1,980 m).
Known for its brightly colored rock formations, the Painted Desert sits on a high, arid plateau that is an expanse of flat-topped mesas, buttes and heavily eroded badland hills with little vegetation. Although it is an austere and barren landscape, the Painted Desert is regarded by many as the most beautiful desert region in North America. The Painted Desert has a yearly rainfall of 5-9 inches (127-229 mm) and extreme temperatures that range from minus-25 to 105 degrees Fahrenheit (minus-31 to 41 degrees Celsius). With such a severe climate, the Painted Desert is largely uninhabited, even though much of it lies within the reservation of the Navajo Indian Nation.
Geologists estimate that the rock formations that make up this area are about 200 million years old. With the passing of time, years of rain, wind, floods, volcanoes and earthquakes have caused this region to become covered by a soft layer of soil that is mostly volcanic ash, sandstone and mud. It is the soft texture of the earth, along with mineral deposits, that has produced the extraordinary colors and erosion effects seen in this terrain.
These forces have produced colors that are a rainbow of hues. Some of the more vibrant colors are red, orange, yellow and pink, and they are caused by a concentration of minerals, such as iron and aluminum, in the soil. This spectrum of colors is seen mainly in the northern end of the area. Other layers of color are paler and are shades of lavender, gray and blue. These are mainly the result of floods or rain removing oxygen from the soil, over eons, and they are more often seen in the southern portion.
The Painted Desert is now designated as a wilderness area. Although there are major highways nearby, much of it is reachable only by unpaved roads or on foot. Visitors can choose from several hikes, and there is a 10-mile (16-km) paved road for non-hikers to use in order to see the rock formations and colors. The colors are most vivid at sunset.