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Devils Tower

Nobody knows how this unusual rock was formed, but geologists have put forth several theories. They agree that Devils Tower is an “igneous intrusion”, which is magma that hardened while still underground. This may have happened 60 million years ago, which is when the Rocky Mountains were forming too. Scientists disagree about how this magma eventually came to tower so high above its surroundings. A popular theory sets Devils Tower as the neck of an old volcano. In this theory, the rest of the mountain eroded away. *Weather continues to erode the tower. Cracks fill with ice and expand, and rocks then fall to the ground. Piles of broken lava columns at the base of the tower indicate that it used to be larger. *Native Americans also have stories to explain Devils Towers. In their stories, the tower is called Mateo Tepee, meaning Grizzly Bear Lodge. The rock’s long vertical cracks reminded people of scratches that a bear might make. In a Kiowa story, for example, seven little girls were playing far from their village when bears started to chase them. The girls ran to a small rock and prayed for it to save them. The rock started to push upwards, higher and higher until the girls were out of the bears’ reach. The bears scratched at the rock and broke their claws. The Kiowa say that these little girls were pushed upward to the sky; they now form a seven-star constellation. Another version of the story has little boys chased by bears, and an eagle carries them home from the tall rock.*Devils Tower appears insurmountable to many. Henry Newt, who was part of area’s first geological survey, wrote in 1875: “Its summit is so entirely inaccessible that the energetic explorer… standing at its base could only look upward in despair of ever planting his feet on the top.” Nonetheless, a Wyoming rancher named William Rogers ascended the tower in 1893; he climbed up with the aid of wooden pegs that he’d drive into cracks. A more professional ascent was made in 1937 by a small party representing the American Alpine Club. The climb can be made relatively easy or extremely challenging according to the path someone chooses. *The tower is still sacred to several Native American Plains tribes, including the Lakota Sioux, Cheyenne, and Kiowa. There have been conflicts between tourists who want to climb the tower and indigenous people who hold ceremonies around the monument. There is now a compromise that involves a voluntary climbing ban in June, which is when the tribes traditionally use the tower most. This compromise has not satisfied everyone, since climbers see the rock as federal land and Native Americans see ascension of the monument as desecration. About 4,000 people climb Devils Tower every year. According to a PBS documentary called In Light of Reverence, most agree not to climb during the month of ceremonies.

The region is also known for its colorful rock layers. The oldest visible rocks have been dated to the Triassic period, or about 200 million years ago. These are dark red sandstone and siltstone, colored by oxidized iron. A thin white band of Jurassic-era gypsum follows. People can also spot gray-green shale, red mudstone, and yellow sandstone.

The United States was probably first aware of Devils Tower after an 1859 Yellowstone expedition led by Captain W. F. Reynolds. In 1875 Colonel Richard Dodge led a geological survey to the rock. It was Dodge who named Devils Tower; he thought that natives called it “Bad God’s Tower”. Congress designated the area a US forest reserve in 1892, and by 1906 it was the country’s first national monument. In addition to the tower, the park includes the Belle Fourche River and 1347 acres of pine forests and grasslands, home to deer, prairie dogs, and other animals.*