From the North Atlantic (Cape Cod National Seashore) to Lake Michigan (Indiana Dunes National Park) to the Gulf of Mexico (Topsail State Preserve in Destin, FL), our campervan has taken us to many wind-swept sand dunes and their associated beaches for fun in the sun and water. We recently visited sand dunes in southern New Mexico unlike any others we’ve explored, and they were far away from the nearest swimming beach.

We initially planned to simply drive through the southwestern portion of New Mexico on our trip west from Florida in February 2021.  At the beginning of the pandemic, the New Mexico State Government implemented strict quarantine and travel restrictions to limit the spread of COVID-19, similar to the New England states. Having quarantined in Vermont last summer, we agreed with the New Mexico’s right to establish emergency restrictions and planned to move onto Arizona. However, in early February, these restrictions were loosened. With our swift travel through Texas, I thought we could take the opportunity to safely spend a portion of one day at White Sands National Park in southern New Mexico and still follow the current New Mexico COVID-19 recommendations.

White Sands National Monument was established in the early 1930’s by President Herbert Hoover (we visited his presidential retreat in Shenandoah last fall, see our account here) and became a National Park on December 20, 2019 our country’s 62^nd National Park). The park is situated in the Tularosa Basin and surrounded by the San Andres Mountains to the west and the Sacramento Mountains to the east. Like the basin and range province in Nevada, the Tularosa Basin is a closed basin (or endorheic basin, my contribution to your crossword puzzle vocabulary) as no water flows out of it.

While Yosemite has its towering granite cliffs and Yellowstone has its powerful geysers, White Sands National Park has the largest gypsum dunefield in the world, covering over 250 square miles. The uniform composition of the dune field creates a stark, monochromatic environment which on the day we visited was framed by a bright blue sky.

The gypsum within White Sands National Park originated within a great sea, the Permian Sea in the Paleozoic Era, about 250 million years ago. Layers of sandstone, limestone, gypsum, and shale were deposited on the sea floor across a large area of the current southwestern United States. The Permian Sea dried up, and subsequent volcanic activity created thick layers of igneous rock covering and preserving the sea deposits. About 70 million years ago, the gypsum-rich deposits of the former Permian Sea were uplifted during the same geologic event that created the Rocky Mountains. Faulting along the Rio Grande Rift about 10 million years ago further exposed the gypsum beds and created the isolated depression now called the Tularosa Basin. Precipitation during the recent ice ages washed gypsum down into the basin and created a huge lake. When the climate changed again and the lake dried up, large quantities of gypsum remained on the basin floor and wind-swept dunes began to form. 

Unlike the white quartz sands in Destin, the coarse shelly sands on Sanibel, the volcanic black sands in Hawaii, and the pink sands of the Bahamas, the white gypsum sands in the Tularosa Basin are unique because gypsum is water soluble. As a comparison, gypsum is 100 times more soluble than limestone. Thus, if there were an ocean shoreline in current day New Mexico, the gypsum would dissolve, and no sand dunes would form. When the small amount of precipitation falls in Tularosa Basin (about 11 inches per year), the water evaporates and leaves behind any gypsum that may have dissolved.

The primary activities in the national park are hiking and sledding. Yes, you can buy a flexible flyer at the park’s gift shop, trudge up the highest (or steepest) dune you can find, and throw yourself down the hill. We skipped this pursuit. We saw many thrill-seeking children, and a few adults, sliding down the slopes. It did not appear to be as heart-stopping as a slide down a New England icy hillside (we remember Pettee’s Hill back in Sharon, MA), but it clearly was a sledding destination where a snowsuit was not needed.

Betsy and I went hiking instead, usually following the trail markers set by the park service. Trails took us to a playa and through the dune field, with park service information boards identifying the limited plant life and animal tracks present. We climbed up, down, and around dunes, our shoes filling with the fine white sand. It was easy to follow the trails – you simply needed to follow the footprints left behind by prior hikers, hoping they knew where they were going.

On our last hike, while on top of a dune, Betsy proposed going off trail, and following a ridgeline to avoid going up and down and up and down the sandy slopes. Unlike other parks where off-trail hiking is not allowed, at White Sands the entire dune field is open to hiking and sledding. I felt a little bit of guilt as we trapsed across unblemished sand, always trying to practice “Leave No Trace” practices when visiting parks, but then realized a high wind event, seemingly a weekly event in the southwest, would soon obliterate our tracks. And while we didn’t sled, I still found the opportunity to quickly bound down a dune face with the sand cascading behind me.

Back at the van after about five miles of hiking, we considered unloading the mountain bikes and riding Dune Drive, an unpaved loop through the dune field. But we were tired and still had some miles to drive before stopping for the day. After a snack, we drove off. Other than briefly going into the visitor center to buy a patch, we had been socially distant from other park users during this short stop in New Mexico.  Next stop, Chiricahua National Monument, nicknamed a “Wonderland of Rocks.” These two geologists are liking the southwest US so far.

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