White Sands National Park

Where it sits. White Sands lies in the Tularosa Basin of southern New Mexico, between the San Andres Mountains to the west and the Sacramento Mountains to the east, about 25 km south-west of Alamogordo on U.S. 70. The park protects roughly 590 square kilometres of the world's largest gypsum dune field, a 710 square kilometre expanse of blinding white sand that shows up clearly from orbit. It became a national monument in 1933 and was redesignated a national park in December 2019. The dunes sit at about 1,200 m, and the surrounding basin has no outlet to the sea - which is the entire reason the park exists.

What built it. Gypsum is water-soluble and almost never survives as sand anywhere with drainage. Here, rain dissolves gypsum out of the surrounding mountains, carries it into a closed basin and leaves it in the ephemeral Lake Lucero at the basin's low point. When that water evaporates, selenite crystals form on the lakebed - some as long as a forearm - and the wind breaks them down and drives the grains north-east into dunes. The sand is cool underfoot even in high summer because gypsum reflects rather than absorbs sunlight. Four dune types occur here, from crescent-shaped barchans on the fast-moving western margin to parabolic dunes anchored by soaptree yucca, which grows its stem upward as fast as the sand buries it. Several species have gone white to match: the bleached earless lizard and the Apache pocket mouse both evolved pale colouring in this basin.

Deep history. In 2021 researchers published radiocarbon dates on human footprints preserved in the ancient lakebed sediments here, placing people in the basin somewhere between 21,000 and 23,000 years ago - during the height of the last glaciation, thousands of years earlier than most accepted timelines for human arrival in the Americas. Follow-up dating in 2023 supported the result. The tracks, made by teenagers and children walking beside mammoth and giant ground sloth trails, are among the most significant archaeological finds in North America this century. They are not on public display, but the visitor centre covers them.

On screen. The dune field's unbroken white horizon is a director's shortcut to alien, post-apocalyptic or purgatorial, and it has been used that way for seventy years. Location shoots here include King Solomon's Mines (1950), Nicolas Roeg's The Man Who Fell to Earth (1976) with David Bowie, the thriller White Sands (1992), Michael Bay's Transformers (2007) and its 2009 sequel, The Men Who Stare at Goats (2009), Year One (2009) and The Book of Eli (2010). Filming permits here are managed alongside the missile range's own schedule, which is why productions tend to work in tight windows.

What you actually see today. Dunes Drive runs 13 km from the visitor centre into the heart of the dune field, the last stretch graded directly across packed gypsum. Five marked trails leave it: the Interdune Boardwalk, a short accessible walkway over the fragile margin; the Playa Trail; the Dune Life Nature Trail, a 1.6 km loop through vegetated dunes; the Backcountry Camping Trail; and the Alkali Flat Trail, 8 km return across raw dunes marked only by posts, with no shade, no water and a genuine risk of disorientation in wind. Sledding down the dune faces on waxed plastic discs, sold and bought back at the gift shop, is the park's most popular activity by a wide margin. The 1930s Pueblo Revival visitor centre is itself a listed historic district.

Practical notes. The park is surrounded by White Sands Missile Range, and both U.S. 70 and the park close for missile tests - typically a couple of times a week, for up to three hours, with little warning. Check the closure schedule before driving out. Carry far more water than seems necessary; the white surface reflects heat upward and sunburn from below is a real phenomenon here. Sunglasses are not optional. Trinity Site, where the first nuclear device was detonated in July 1945, lies about 100 km north on the missile range and opens to the public only on a handful of scheduled days each year.

Getting there and timing. Alamogordo is 25 km east, El Paso about 145 km south and Las Cruces 85 km west. October to April gives daytime highs of 15C to 25C; May to August routinely exceeds 35C, and spring winds can produce blowing-sand conditions that shut the trails. The park runs ranger-led sunset strolls and full-moon night walks, both of which are the best way to see the dunes - low sun turns the surface into a field of blue shadows and cream ridgelines that midday light erases completely.