Unusual to say the least, this near vertical rock slide is located in the Yellowstone River Valley. Standing at a height of 125 feet, the Devils Slide was named by the Washburn-Langford-Doane Expedition in 1871. Thought to be made of cinnabar, a red mercury ore, cinnabar is still used in naming the mountain surrounding the Devils Slide.
     Today, geologists have not only identified the iron-impregnated rock of this odd slide, but traced its underlying cause. Located between the Gallatin Mountains and the Absaroka Range, this area of the continent was once a huge low-lying inland sea. Armed with a great understanding of plate tectonics, geologists have described a gradual uplift of a broad tract of this Cretaceous Period marine sediment, a layered area that was well compressed over time. Part of the Rockies chain, these vertical beds occurred all along the Gardiner Thrust Fault, from Devils Slide to a point near Mount Everts.
     This section of the Beartooth Mountains is just a part of the dramatic Beartooth and Yellowstone scenery. One can only imagine these imposing mountain ranges before they were reshaped and worn away by erosion for millions of years.