White Sands National Park

White Sands National Park protects the world's largest gypsum dune field, covering roughly 275 square miles of the Tularosa Basin. Gypsum, or calcium sulfate, is rarely found as sand because it is highly soluble in water and is typically carried to the ocean before it can accumulate. The Tularosa Basin is a closed basin with no outlet to the sea, allowing gypsum to accumulate over millions of years. The process begins in the San Andres and Sacramento Mountains to the west, where rain and snow dissolve gypsum from rock. The mineral-rich water flows into the basin and accumulates in Lake Lucero and Lake Otero, where it evaporates, leaving selenite gypsum crystals. These crystals, some growing up to three feet long, are then broken into sand-sized grains by wind, freeze-thaw cycles, and weathering. Prevailing winds from the southwest carry the grains northeast, forming dunes that migrate slowly across the basin at a rate of roughly 30 feet per year. The dunes take several forms, including crescent-shaped barchan dunes, parabolic dunes, and dome dunes, depending on wind patterns and vegetation cover.

The Dunes Drive is an eight-mile paved and unpaved road that leads from the visitor center into the heart of the dune field, with several pullouts and trailheads. The Interdune Boardwalk is an elevated 0.4-mile accessible path through the dunes, offering interpretive panels about the ecosystem. The Alkali Flat Trail is a 5-mile round trip across the dunes to the edge of the ancient Lake Otero bed, the most challenging trail in the park, as it traverses deep sand with no shade. The Dune Life Nature Trail is a 1-mile loop through more vegetated dunes, offering opportunities to spot wildlife and endemic white species. Sledding down the dunes is a popular activity, and wax-coated plastic sleds are available for purchase at the visitor center gift shop. The park offers ranger-guided sunset strolls and full moon hikes, which provide stunning views of the dunes under changing light. For overnight visitors, backcountry camping is available at ten primitive sites located roughly one mile from the road, accessible by hiking through the sand, with permits available at the visitor center.

White Sands National Park is located in southern New Mexico, roughly 15 miles southwest of Alamogordo, the nearest town with full services, and roughly 55 miles northeast of Las Cruces. The park is accessed via Highway 70, which runs between Alamogordo and Las Cruces and passes through the park. Entrance fees are $25 per vehicle, valid for seven days. The visitor center, built by the Civilian Conservation Corps in the 1930s, offers exhibits, a bookstore, and restrooms. There is no lodging inside the park, and the only campground is the backcountry sites accessible by hiking. Lodging and dining are available in Alamogordo and Las Cruces. Because the park is surrounded by White Sands Missile Range, the park is occasionally closed for missile testing, sometimes for a few hours and sometimes for a full day, and visitors should check the park website or call ahead before traveling. The nearest airport is in El Paso, roughly 90 miles to the south, with the Alamogordo-White Sands Regional Airport offering limited service. Cell service is available near the visitor center but limited within the dune field.

White Sands National Park is a year-round destination, but conditions vary dramatically. Summer temperatures routinely exceed 100 degrees, and the white sand reflects sunlight, intensifying the heat and glare. Hiking should be limited to early morning or evening, and sun protection including sunglasses, sunscreen, and a hat is essential. The sand can also reach 140 degrees in direct sun, so shoes are necessary. Spring and fall are ideal, with moderate temperatures and comfortable hiking conditions. Winter is cold, with daytime highs in the 50s and nighttime lows below freezing, and the dunes can be striking with snow cover. The park is a designated International Dark Sky Park, offering exceptional stargazing, particularly during full moon nights when the dunes are lit by moonlight. The dunes support a unique ecosystem with endemic species found nowhere else, including the bleached earless lizard, White Sands woodrat, and several species of white moths and beetles that have evolved pale coloration for camouflage. The park also preserves the oldest known human footprints in North America, dating to roughly 23,000 years ago, discovered in the margins of ancient Lake Otero.