Red-blue anaglyph of cave ruins in bluffs of San Juan River, Utah.  Based on public domain USGS image taken 1875 by William H. Jackson.
<a href="//commons.wikimedia.org/wiki/User:Jstuby" title="User:Jstuby">Jstuby</a>
2020-10-29
<span class="int-own-work" lang="en">Own work</span>