Steven Dutch, Professor Emeritus, Natural and Applied Sciences, University of Wisconsin - Green Bay
As the wind sweeps across the remote San Luis Valley in Colorado, it picks up sand. On the east side of the valley, the Sangre De Cristo Range funnels the wind through a low pass, Medano Pass. The bare peak with the patches of snow on the north side of the pass is 13,300 foot Mount Herard, but the pass itself is only about 8,000 feet. Outside the picture, to both the north and south, the mountains reach over 14,000 feet. As the air rises to go over the pass, it loses speed and drops its load of sand. The tiny trickle of water in the foreground is called Medano Creek and had a peak flow in 2007 of only 35 cubic feet per second. Nevertheless, it maintains the sharp boundary of the dunes, since sand that blows into the stream is carried back out into the valley. Everything across the stream has been designated a wilderness area, making it possibly the only wilderness area you can hike to in your bare feet.
Mount Herard is located at 37o 50' 58" N, 105o 29' 41" W. The picture viewpoint is 37o 50' 24" N, 105o 31' 06" W.
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Created 17 December 2007, Last Update 15 January 2020