Alamogordo, New Mexico
White Sands Missile Range encircles the monument, and Holloman Air Force
Base lies to the east.
Rising from the heart of the Tularosa Basin is one of the world's great
natural wonders - the glistening white sands of New Mexico. Here, great
wave-like dunes of gypsum sand have engulfed 275 square miles of desert and
created the world's largest gypsum dune field.
White Sands National Monument preserves a major portion of this unique
dune field, along with the plants and animals that have successfully adapted
to this constantly changing environment.
Gypsum is rarely found in the form of sand because it is water-soluble.
Normally, rain would dissolve the gypsum and carry it to the sea. Since the
Tularosa Basin has no outlet to the sea, rain that dissolves gypsum from the
surrounding San Andres and Sacramento Mountains is trapped within the basin,
and the rain either sinks into the ground or forms shallow pools which
subsequently dry out and leave gypsum in a crystalline form, called selenite,
on the surface.
Unlike dunes made of quartz-based sand crystals, the gypsum does not
readily convert the sun's energy into heat and thus can be walked upon
safely with bare feet, even in the hottest summer months.