Devils Tower was the first United States National Monument, established on September 24, 1906, by President Theodore Roosevelt. The monument's boundary encloses an area of 1,347 acres.
The name Devil's Tower originated in 1875 during an expedition led by Colonel Richard Irving Dodge, when his interpreter reportedly misinterpreted a native name to mean "Bad God's Tower". All information signs in that area use the name "Devils Tower", following a geographic naming standard whereby the apostrophe is omitted.
The landscape surrounding Devils Tower is composed mostly of sedimentary rocks. The dark red sandstone and maroon siltstone, interbedded with shale, can be seen along the Belle Fourche River. Oxidation of iron minerals causes the redness of the rocks. This rock layer is known as the Spearfish Formation.
Created as sea levels and climates repeatedly changed, gray-green shales (deposited in low-oxygen environments such as marshes) were interbedded with fine-grained sandstones, limestones, and sometimes thin beds of red mudstone. This composition, called the Stockade Beaver member, is part of the Sundance Formation. The Hulett Sandstone member, also part of the Sundance Formation, is composed of yellow fine-grained sandstone. Resistant to weathering, it forms the nearly vertical cliffs that encircle the Tower.
In recent years, climbing Devils Tower has increased in popularity. The first known ascent of Devils Tower by any method occurred on July 4, 1893, and is accredited to William Rogers and Willard Ripley, local ranchers in the area. They completed this first ascent after constructing a ladder of wooden pegs driven into cracks in the rock face. A few of these wooden pegs are still intact and are visible on the tower when hiking along the 1.3-mile (2.1 km) Tower Trail at Devils Tower National Monument. Over the following thirty years many climbs were made using this method before the ladder fell into disrepair.
The Tower is sacred to several Plains tribes, including the Lakota, Cheyenne and Kiowa. Because of this, many Indian leaders objected to climbers ascending the monument, considering this to be a desecration. The climbers argued that they had a right to climb the Tower, since it is on federal land. A compromise was eventually reached with a voluntary climbing ban during the month of June when the tribes are conducting ceremonies around the monument. Climbers are asked, but not required, to stay off the Tower in June.
*Location: 2,365 Km west from Washington D.C.
*Duration: One day.
*Best time: Summer.