Check out these stunning photos of natural sandstone arches in the American Southwest. These incredible geological formations are a reminder of the power and beauty of nature.

Nature's archway

Arches and natural bridges are two types of geological formations that have always held an irresistible attraction to those who enjoy the beauty of naturally sculptured stone. Thousands of arches and natural bridges are found in landscapes all around the world. All are a testament to one of nature's most powerful and persistent forces – the process of erosion. Shown here is the natural Rainbow Bridge in the Glen Canyon National Recreational Area of southeastern Utah. It was created by the action of running water flowing beneath it. (Credit: NPS)


Landscape from erosion

In this high desert region of the American Southwest, arches and natural bridges are common in the soft red sandstone. Some 300 million years ago, these vast lands were covered by shallow, inland seas that refilled and evaporated approximately 29 different times. Over the millennia, the ebb and flow of ancient seas, and the resulting actions of geological forces, have created a landscape where the effects of erosion have carved the beautiful arch and bridge formations found today. (Credit: Linda & Dr. Dick Buscher)


Set aside

One special part of this western land, known as Arches National Park, has been set aside to preserve the densest cluster of natural stone arches found anywhere in the world. Here in this southeastern part of Utah is a fabulous 120-square-mile (310 square kilometers) park that protects and preserves 2,500 documented natural stone arches and a few small natural bridges. Turret Arch is shown here. (Credit: Linda & Dr. Dick Buscher)


A collection of sculptured rock

This great collection of sculptured rock scenery found at Arches National Park is the result of the actions of 100 million years of extreme temperatures, water, ice and the movement of 1,000-feet-thick (305 meters) deposits of salt left behind by those ancient seas. Covering these vast salt deposits are miles of thick layers of Jurassic Entrada and Navajo Sandstone that, over the years, were first weathered and eroded into many freestanding rock structures known as "fins," shown here. (Credit: Linda & Dr. Dick Buscher)


A constant barrage

The small grains of sand that make up these sandstone fins are always under attack by wind, rain and extreme temperatures. This constant assault by the elements of nature results in the weakening of the naturally cemented grains of sand, thus causing whole chunks of rock to break and fall. Many fins totally collapse under this relentless natural attack. But, some fins are hard enough and balanced enough to create the amazing arches seen in the national park today. Double Arch is shown here. (Credit: Linda & Dr. Dick Buscher)


Requirements for the title

To qualify as an arch, the opening under the stone must be at least 3 feet (1 m) long in any direction. There is no requirement as to how thick a rock opening must be to qualify as an arch. The longest arch found today in Arches National Park is called Landscape Arch, shown here, which measures 306 feet (93 m) between the two bases. New arches are always being formed, while older arches occasionally collapse and fall. (Credit: NPS)


Other cool shapes

Sometimes the forces of erosion create other rock formations known as windows, spires, towers, hoodoos and balance rocks, shown here, in the red sandstone of Arches National Park. These spectacular rock structures have captured the human imagination since they were first seen. They have been associated with everything from gods to Hollywood cartoon characters. (Credit: Linda & Dr. Dick Buscher)


Green beauty

Vegetation found across this sculptured sandstone landscape is dominated by gnarly pinyon and junipers trees. Their deep green foliage remains year round and is accented each April to July with a wide variety of colorful wildflowers. The Skyline Arch, a Utah Juniper (Juniperus osteosperma) and a variety of high desert wildflowers are shown here. (Credit: Linda & Dr. Dick Buscher)


Life of the party

The fauna of this national park is typical for high desert regions across the American Southwest. Mule deer, kit fox, jackrabbit and cottontails all make their homes in this dry environment. The calls of pinyon jays (Gymnorhinus cyanocephalus) and common ravens (Corvus corax) echo among the rock canyons and sculptured arches throughout the park. Many lizard species, such as this collared lizard (Crotaphytus collaris) gather the warmth of the afternoon sun while sitting atop sandstone boulders. (Credit: Linda & Dr. Dick Buscher)


Famous arches

All of the most prominent arches within the national park have been given names. The most famous of the natural arches found in Arches National Park is called Delicate Arch. This 65-foot-tall (20 m) sandstone wonder has become the State of Utah's most famous icon, appearing on license plates, magazine covers and outdoor advertisements. The formation was named Delicate Arch in 1934. Prior to that, local cowboys called the arch "the Chaps." (Credit: Linda & Dr. Dick Buscher)


Nature's best creations

The natural arch treasures found in this region of the American Southwest are a vibrant collection of nature's best creations. The oxidation of iron found within the sandstone has created a red tapestry-type landscape that is further enhanced when silhouetted against the brilliant blue western sky. Geologists suggest that we live in the perfect time to see and enjoy the many arches now found in this land, as nature's many forces will continue to create and then destroy these marvelous rock formations. (Credit: Linda & Dr. Dick Buscher)

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