This cool looking tower is visible from some points of the road while approaching the Devil's Garden trailhead. This was one of the first towers climbed in Arches, by the 60's hardguys Rearick and Kamps.
Getting There
Easy, flat 2 mile approach past many cool arches. From the Devil's Garden trailhead parking lot, follow the signs to Double O arch. At this point, you'll see a sign for the Dark Angel which will be visible from here.
Cool find if you're into petroglyphs: head pretty much due south/southeast of the tower and you will soon come to a short cliff. Find a way down and explore east and west until you find them. See the photo of the moose posted above. Please heed the signs about traveling lightly and with care. The location of these are not publicized by the Park.