Devils Tower National Monument Professional Review and Guide
"Long before it gained additional notoriety from the motion picture Close Encounters of the Third Kind, Devils Tower was one of the most recognizable landmarks, not only in Wyoming, but in the entire country. It is not difficult to understand why. Rising 867 feet (1,267 feet above the Belle Fourche River), this gigantic monolith is visible, on clear days, from as far as 100 miles away! Other statistics are equally staggering. The tower is estimated to be 50 million years old. At its bottom it is almost 1,000 feet across, but it narrows as it rises so that at the very top it measures only 275 feet across. Although many people climb it (we’re told that it is much easier than it looks), you won’t be doing so as a casual visitor.
The tower itself is quite beautiful, despite having been described most often as a gigantic stone tree stump (indeed, its many fluted columns do give that effect). It is certainly among the most unusual of the many geologic formations in the country. This eTrail explains in detail how to tour the park. In addition to a park map the details include driving tours, outdoor recreation, accommodations, campgrounds, dining, and more."