Hiking to the top of the Great Sand Dunes was one of the best parts of our trip. I used my iPhone 4 to shoot parts of the hike. If you ever get the chance to make it to the top of the dunes I highly recommend you take the opportunity. Took up a little over an hour of walking in the sand. The large, main dune field covers approximately 30 square miles and rises just under 1000 feet of climbing elevation. ALL ON SAND!