The Great Sand Dunes National Park in Colorado is a fascinating place. The park contains the tallest sand dunes in North America, rising to a maximum height of 750 feet from the floor of the San Luis Valley on the western base of the Sangre de Cristo Range, covering about 19,000 acres. Researchers say that the dunes started forming less than 440,000 years ago. In this photo, Medano Creek flows in curious pulses along the southeast edge of the dunes, while snow covered peaks of the Sangre de Cristo rise behind.
Panasonic GX8, Olympus 9-18mm lens @ 18mm, ISO 400, f/14, 1/100″ exposure.