Great Sand Dunes. Photo © Jim Doty Jr.

Great Sand Dunes National Park has the tallest dunes in North American. The prevailing west winds blow the sand across the San Luis Valley where it collects at the base of the Sangre de Cristo mountains. The Park is in south central Colorado. From Denver you can take a scenic 5 hour drive via US 285 and CO-17. It is a great place to take pictures and I prefer to go in the fall and spring. The best light is early and late in the day when the sun throws dramatic shadows across the dunes. This photo was taken from the entrance road.

Info about the park is here.

Data: Canon 5D, EF 24-105mm lens at 105mm. Shutter: 1.40. Aperture: f/11. ISO: 100.