<a href="https://en.wikipedia.org/wiki/Great_Sand_Dunes_National_Park_and_Preserve" class="extiw" title="en:Great Sand Dunes National Park and Preserve">Great Sand Dunes National Park and Preserve</a>, at the east end of the <a href="https://en.wikipedia.org/wiki/San_Luis_Valley" class="extiw" title="en:San Luis Valley">San Luis Valley</a> in Colorado, flanked by the spine-like <a href="https://en.wikipedia.org/wiki/Sangre_De_Cristo_Mountains" class="extiw" title="en:Sangre De Cristo Mountains">Sagre De Cristo Mountains</a>
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/52614599@N00">Doc Searls</a> from Santa Barbara, USA
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<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/docsearls/16669169237/">2015_02_10_lax-ewr_435z</a>