Great Sand Dunes National Park & Preserve, Mosca, Colorado

Great Sand Dunes National Park was established in September 2004. Before 2004 it was a national monument. Our first trip to the Dunes was in 1993. There was quite a bit more greenery and the Medano creek was running. We camped near the Dunes and since becoming a national park, it has been completely redone. New campgrounds have been built, a Visitor Center established and a picnic area with access to the Dunes. I think it was the picnic area where we first camped back in 1993. We took our nephew Jonathan on our first trip. Below are a few of our pictures from the 1993 trip.

Josh & Jonathan

Gayle in front with Jacklyn on her back

Our second trip to the Dunes was in 2001, and on this trip we took our other nephew, Justin (Jonathan's brother).

Jim & Justin

Jacklyn in front

The origins of the Dunes are from wind and sand moving continuously, which form the dunes. Most sand comes from the San Juan Mountains, over 65 miles to the west. Larger, rougher grains and pebbles come from the Sangre de Cristo Mountains, which are to the east of the dunes. Sand and sediments from both ranges washed into a huge lake once covering the valley floor. As the lake reduced, prevailing southwesterly winds bounced the sand grains to be piled up beneath the Sangre de Cristo or washed back toward the valley floor. North-easterly storm winds blast through mountain passes, piling dunes back on themselves and creating North America's tallest dunes. The dunes are probably less than 440,000 years old.

Congress has protected nearly 90% of Great Sand Dunes National Park and Preserve as wilderness under the 1994 Wilderness Act. The Wilderness is 33,549 acres in the national park, and 41,676 acres of the national preserve are in the Sangre de Cristo Wilderness. Our final trip to the dunes was in 2018.

We visited the Dunes Saturday evening with the western sun hitting the western sides of the dunes. If you look closely at some of the above pictures, you will see people walking up the dunes. They look like ants. We are not camping in the park, but at a campground about 4 miles outside of the park. The elevation where we are is 8,062 feet. We went to the Visitor Center on Sunday and that afternoon I ventured a walk up the dunes. I made it half way up the dunes and decided to turn around. It was quite a chore just getting up that far. Jim did not come. Dogs are even allowed on the dunes as well as sand surfing. The hotel rents boards so people can sand surf. 

I also got a couple of beautiful sunset pictures.

As part of the preserve, there is a large area with its entrance right across the street from the RV Park we were staying at. I was able to take the dogs with me and walked a good distance into the preserve. As it was before sunrise, I was able to take some neat pictures of the dunes as they change with the rising sun.

Also, in the spring and early summer the Medano creek runs through the dunes so one has to walk through the water to get to them.  I recall that the stream was running on one of our first trips to the dunes, but this last time it was bone dry.

On the sandy creek bottom, the fast-flowing current pushes sand grains into small underwater ridges, called "antidunes." Like dams, antidunes trap water, until they finally break, sending waves of water downstream.