Tower of Petroglyphs
This petroglyph panel from the Formative Period (A.D. 1 to A.D. 1275) is found along the Potash-Lower Colorado River Scenic Byway just outside of Moab, UT. The anicent rock art extends along the base of this towering cliff for a good 125 feet in the darkened area you can see above, it truly is some of the most impressive petroglyphs I've ever seen.
Image Notes: 7-frame HDR. I do have some closeups of this rock art, I will hopefully get some of them posted somewhere down the line.