“… sea in a storm, except as to color.” – Zebulon Pike, 1830
The dunes probably were created by the brisk winds that blow back and forth across the San Luis Valley, and are ever changing.
As sunset casts golden light and eerie shadows across the vast landscape, no visitor can resist taking a picture of Great Sand Dunes National Park & Preserve near Alamosa.
These are the tallest dunes in North America, topping out at 750 feet above the park’s 8,200 feet in altitude. The dune field itself lies in the San Luis Valley of Colorado, flanked by the Sangre de Cristo Mountains on the east, with the San Juans in the distance to the west. No, there’s no ocean. This unique geological feature is surrounded by the Colorado Rockies.
“I call it Colorado’s beach,” says Libbie Landreth, a now-retired park ranger who spent most of her career in the park and still lives nearby.
While the obvious attraction is the dunes themselves, Landreth always encouraged visitors to explore the other aspects of the park, such as the two water courses (Medano and Mosca creeks), the mountainous wildlife preserve and the sand flats.
Visitors can hike the dunes (not easy, and made more difficult by the park’s altitude) or trails along the edge of the dunes and up into the preserve, which ascends to the ridge line north of the park. Here, other hikers walk their dogs, shoot photos or play in the sand.
On a sunny but cool spring Sunday, a group of students from nearby Adams State College in Alamosa try their luck with “sledding’’ down the slopes. They take a run, drop belly first on the mats – and stick. The rubber mats won’t slide, and they roll around, laughing at their folly. Across the sandy valley on another dune, a young family has better luck with a hard plastic saucer-sled. But the climb back up is akin to walking up a ski slope for a few seconds of thrills.
Skiers and snowboarders tend to have the most success – especially right after a rain or snowfall. One would think that such activity would damage the landscape, but it doesn’t – it’s constantly shifting and changing anyway. Just stay off the vegetation, rangers will warn. It’s fragile.
Visitors also can explore a number of life zones in a relatively small area – from the wetlands and riparian habitat surrounding the creeks to the alpine tundra at the top of the nearby 13,000-foot peaks.
The dunes themselves encompass 30 square miles. Add to that the preserve and other adjacent land purchased to complete the park, for a total of 233.6 square miles full of mule deer, pronghorns, elk, bighorn sheep, mountain lions, bears, coyotes, raccoons, marmots, rabbits, pikas, kangaroo rats and several odd species of insects
Head up the four-wheel-drive Medano Pass Road to a spot dubbed Point of No Return to encounter mule deer and easier (much firmer) hiking trails. Check out the giant Pondersosa pines, scarred by the American Indians (primarily the Utes) who once frequented this area and used the bark for medicine.
The dunes are accessible all the time, year round. The visitor’s center is open daily with exhibits, displays and a film. Plenty of campsites in the treed area near the dunes accommodate those who want to spend a night, or more.
The park itself never closes. But visitors are warned to stay out of the dune field on hot summer afternoons; the surface temperature of the sand can get anywhere from 140 to 150 degrees on sunny July days. By contrast, the snow often melts off within a few hours after a winter or spring storm, making the dunes a pleasant hike on a cool day.
Another unusual aspect of the park is the wavelike action found in Medano Creek each spring. The water flows in pulses, not a steady stream, and is so shallow anyone can wade – most of the time.
Some years, the water is high enough (a foot or more deep) for kids to body surf on the waves or pulses, Landreth says. And don’t forget it’ll be cold, she adds: “After all, it is snowmelt.”
Medano Creek flows best during spring thaw, from April until early June. That’s when water birds make their annual appearance. Unfortunately, it’s also the season for flying insects. Pack insect repellant.
How the dunes were formed here seems like a mystery, but not to anyone who’s ever experienced the fierce winds that can sweep across the San Luis Valley. Sand blows straight sideways, with the prevailing wind coming from the southwest. Gradually, the dunes could have been formed as recently as 12,000 years ago. And though they appear as volatile as the turbulent sea to which explorer Zebulon Pike compared them, their basic profile hasn’t changed in more than 100 years. A photo taken in 1874 and another taken in 1999 show a very similar sand-scape profile.
“People come to Colorado expecting to see mountains,” Landreth says. “This is just so unexpected.”