White Sands National Park

Gypsum almost never forms sand dunes, because it dissolves in water. In the closed Tularosa Basin of southern New Mexico, where no river drains to the sea, it has built the largest gypsum dunefield on Earth, about 275 square miles (710 km²) of brilliant white waves. The gypsum washed down from the surrounding mountains into an Ice Age lake, crystallized as the lake dried, and was ground into sand by wind that still pushes the dunes across the basin. The sand stays cool underfoot even in summer, and several moths, lizards and mice here have evolved pale coloring.

President Herbert Hoover proclaimed White Sands National Monument in 1933, and Congress redesignated it a national park on December 20, 2019. The park protects about 229 square miles (592 km²), the southern part of the dunefield, and is entirely surrounded by White Sands Missile Range, which occasionally closes the road for tests. Its dried lakebeds hold the largest known collection of fossilized human footprints, which researchers have dated to between about 21,000 and 23,000 years ago, pushing back the accepted date for people in North America.

• New Mexico
  The Land of Enchantment, high desert and southern Rockies located in
• The Chihuahuan Desert
  The largest desert in North America located in
• El Paso
  A desert border city at the pass of the Rio Grande near
• Trinity Site
  Where the first atomic bomb was detonated near