A term inspired by castellated erosional forms in the western deserts, though the castle rocks of the upper Missouri River, commented on by Lewis and Clark and rendered in watercolor by Karl Bodmer in 1832, are among the most widely known examples of the form. Utah geologist Lee Stokes claims there are as many Castle Rocks in the American Southwest as there are Inspiration Points in the country’s national parks. He goes on to say, in Scenes of the Plateau Land and How They Came to Be, that the related term monument is more properly “applied to those ﬁnal remnants [of a previously massive rock structure] that are much higher than they are wide and which therefore bear some resemblance to living things or the works of man.” Castle rock incorporates within its designation features typical of such formations: a broad palette of ocherous hues, vertical and horizontal banding, grooves and knobs, and turreted heights. According to some, a castle rock differs from a monument rock in that it stands more obviously within or upon the structure of its parent rock, not in isolation in an otherwise open landscape. Its towering shape can easily be imagined as having once been a section in a solid rock wall, which, eroded by water and wind, became a mesa, then a butte, and ﬁnally a spire. A well-known Castle Rock—also called locally Castleton Rock—stands as a sandstone beacon on the eastern boundary of the town of Castle Valley, Utah, an icon in the Colorado Plateau’s Redrock Wilderness and a destination for rock climbers worldwide.